Sincript

A single, menu-driven batch script (PerfTweaks.cmd) that applies a curated, reversible set of performance, privacy, and maintenance tweaks for Windows 10 and Windows 11.

Everything is opt-in from a menu, every registry change is backed up before it is made, and the script can create a System Restore Point and a full registry export on request. There is no silent "apply everything" — you choose what runs.

The script also detects at startup whether it is running on a laptop or a desktop (ACPI battery presence — one registry query, no WMI/PowerShell; shown as Machine= on the main menu and in the log). Actions that are typically counterproductive on the detected machine class — the always-on power plan, hibernation off, BCD dynamic-tick off, and the timer-resolution autostart on laptops; LargeSystemCache on desktops — print an [ADVISORY] line before their confirmation prompt. The SysMain toggle works the same way against a different probe: it checks what the Windows disk actually is (SSD vs mechanical) and warns first, because SysMain genuinely helps a spinning disk. That check asks the drive directly — does it incur a seek penalty, which is literally the SSD-vs-spinning question and what Windows itself uses — rather than going through the Storage WMI cmdlets, which fail on more machines than you'd expect (one faulty vendor storage provider takes the whole namespace down with it, and OEM laptops ship those as standard). Advisories are informational only: they never block an action, never change a default, and never alter what a preset applies.

The runtime is a single self-contained PerfTweaks.cmd (no installer, no dependencies). The release also ships optional bundled inputs, a timer-resolution helper, an example custom preset, and a developer test harness — see Release contents.

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Release contents

Path	Role
PerfTweaks.cmd	The tool — copy this anywhere you want to run it
SetTimerResolution.exe	Optional timer-resolution helper for the action
boot.config, hosts	Optional inputs for the Unity and hosts actions (place next to the script)
sincript_presets/	Folder for custom .preset files; includes example.preset
tests/	Static-analysis harness (Run-Tests.ps1) — for development/CI, not needed on end-user PCs

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Requirements

• Windows 10 or Windows 11 (tested on recent builds, including 24H2 / build 26100).
• Administrator rights for the full feature set. The script auto-elevates: on launch it requests elevation through UAC and relaunches itself elevated. Approve the prompt for HKLM changes, services, BCD edits, restore points, and similar.
• If you decline UAC (or elevation probes are unavailable), the script warns and asks whether to continue in limited mode — only per-user (HKCU) tweaks and read-only status screens work reliably there; privileged actions report [WARN] instead of a misleading [OK].
• No installation beyond copying the files you need.

How to run

1. Place PerfTweaks.cmd anywhere (Desktop, a USB stick, etc.).
2. Double-click it (or right-click → Run as administrator).
3. Approve the UAC prompt.
4. Use the number keys to navigate the menu, then press Enter.

Recommended first step: open 8. Backups & status and create a System Restore Point and/or a full registry backup before applying anything.

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Menu overview

Main menu

#	Item	What it covers
1	Cleanup & repair	Temp/log cleanup, SFC/DISM, Windows Update reset, Store repair, WinSxS compaction
2	Performance tweaks	GameDVR off, game-task priorities, snappier UI timings, optional Game Mode / Game Bar overlay residual / mouse-acceleration / file-extensions / Storage Sense / Search-scope / SysMain toggles
3	Privacy & telemetry	Telemetry, ad ID, Cortana/web search, location, activity history, feedback off; Windows AI (Copilot, Recall, Click to Do) and inking/typing/speech personalization off; Win11 quiet surface (extra Start/lock tips, search-box suggestions, tailored experiences); optional firewall block for the telemetry service; optional Edge first-run / sidebar / shopping nudges
4	Power plan	High-performance / Ultimate plan, disable sleep & disk timeouts, optional 5% min processor state
5	Network & DNS	TCP tuning, DNS provider switch, full network stack reset
6	Apps & files	OpenAsar for Discord, Unity boot.config, custom hosts file, lightweight Steam launcher, Windows timer resolution, startup-apps manager
7	Advanced	At-your-own-risk items: CPU mitigations, boot timers, NVMe flags, IPv6, memory compression, GPU telemetry
8	Backups & status	Restore point, full registry export, current-status report, single-value .reg restore, backup-folder manager
9	Apply recommended safe set	One-click core tweaks from categories 1–5 (no prompts)
10	Presets	Auto-apply light / moderate / heavy preset, build your own custom preset, or restore a preset's JSON backup
11	What was excluded	Explains what the script deliberately leaves out, and why
12	System tools	General-purpose tools, not tweaks: PATH editor and find what is locking a file
0	Exit

Sub-menus

• Cleanup & repair — Disk cleanup (with an optional, irreversible clear of all Event Viewer logs) · SFC + DISM repair (their native progress output now streams live to the console) · Windows Update reset · re-register Microsoft Store · compact WinSxS.

  Every delete in the cleanup is anchored on an environment variable (%TEMP%, %SystemRoot%, %LocalAppData%), and each of those is checked before anything is deleted: it has to be set, point at a folder that exists, and not be a drive root. Anything that doesn't check out is skipped, out loud. That guard is there because batch doesn't complain about an unset variable — it expands to nothing — so on a machine with a broken environment del /f /s /q "%TEMP%\*.*" would quietly become del /f /s /q "\*.*": a recursive delete from the root of the drive. Quoting the paths doesn't help; the quotes are intact, it's the contents that collapsed.

• Performance tweaks — GameDVR / policy off and gaming MMCSS priorities (core) · optional SystemResponsiveness / network throttling / Win32PrioritySeparation / LargeSystemCache · optional Game Mode and Game Bar overlay residual (recording is already off in core; the overlay prompt is separate and does not uninstall Xbox) · mouse acceleration / file extensions / Storage Sense / Search scope / SysMain / verbose boot status.

• Privacy & telemetry — Telemetry / ad ID / Cortana / activity / location / Windows AI (Copilot, Recall, Click to Do) · Win11 quiet surface (extra Start/lock Content Delivery tips, search-box suggestions, tailored experiences) · optional per-user sync-service disable · optional DiagTrack firewall block · optional Edge first-run / hubs sidebar / shopping nudges (Edge only; does not uninstall Edge).

• Network & DNS — Apply TCP tweaks (autotuning, RSS/RSC; optional Nagle / delayed-ACK off for lower latency, and optional Delivery Optimization off so Windows Update stops uploading files to other PCs) · DNS menu (Cloudflare, Google, Quad9, or back to automatic/DHCP) · reset network stack.

• Apps & files — Install OpenAsar · apply a Unity boot.config · apply a custom hosts blocklist · restore the original hosts · install SteamLight (a lightweight Steam launcher + Desktop shortcut) · apply/remove a higher timer resolution (SetTimerResolution autostart) · remove built-in Store apps (debloat) · manage startup programs (flip Run-key and Startup-folder entries between Enabled and Disabled via the same reversible StartupApproved switch Task Manager uses; the prior state is saved to a .reg backup before every flip).

• Advanced — Disable/enable CPU mitigations · set/revert boot (BCD) timers · NVMe feature flags · disable IPv6 · disable memory compression · disable GPU telemetry (NVIDIA telemetry tasks + registry, or the AMD User Experience Program opt-out) · GPU hardware scheduling (HAGS) on/off · set a permanent per-program CPU priority (per .exe, via Image File Execution Options).

• Presets — Apply a built-in light, moderate, or heavy preset (no per-item prompts) · apply a custom preset from a .preset file · restore the registry values a preset changed from one of its JSON backups.

• System tools — Edit PATH (System or User) with dead-entry and duplicate cleanup · Find what is locking a file and optionally close the holder. Both are described under System tools.

• Backups & status — Create a System Restore Point · export HKLM + HKCU · restore from a preset JSON backup · restore a single value backup (.reg) · manage/open the backup folder · show the current state of key tweaks, the active power plan, hibernation, minimum processor state, DNS, TCP autotuning, GPU hardware scheduling (HAGS), memory compression, the hosts line count, and whether OpenAsar is installed.

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Presets

10. Presets applies a whole bundle of tweaks in one go, with no per-item prompts (only a couple of yes/no questions — restore point, and DNS choice where relevant). There are three built-in presets plus your own custom presets.

Preset	What it applies	DNS
Light	Cleanup core (temp/log cleanup, DNS flush), privacy/telemetry core, network core (TCP autotuning, RSS/RSC). Nothing risky.	Asks (Cloudflare / Google / Quad9 / skip)
Moderate	The full recommended safe set (cleanup + privacy + performance + power + network cores) — same as menu item 9. Optionally installs OpenAsar (bundled app.asar if present, otherwise downloads the latest nightly).	— (uses the safe set; DNS unchanged)
Heavy	Everything in the safe set plus foreground/latency tuning: SystemResponsiveness = 0, network throttling off, Win32PrioritySeparation = 42, Game Mode off, Nagle off, IPv6 off, NVMe flags, GPU telemetry off, BCD timers, memory compression off.	Asks (Cloudflare / Google / Quad9 / skip)

Heavy deliberately does not include CPU-mitigation changes, network-stack reset, system repair (SFC/DISM), debloat, LargeSystemCache, or the timer-resolution autostart — those stay manual under their own menus. Heavy shows a warning and offers a restore point first.

Preset backups (JSON)

Manual menu actions each write their own tiny .reg backup. Presets are different: every registry value a preset changes is recorded into one JSON file in Documents\PerfTweaks_Backups, named Preset_<name>_<random>.json. The script prints the exact path when the preset finishes.

To put those registry values back, use 8. Backups & status → 4. Restore from a preset backup (JSON) (also reachable from the Presets menu). It reads the JSON and, per value, either restores the previous data or deletes the value if it didn't exist before.

The JSON backup covers registry values only. The non-registry parts of a preset — power plan, DNS, BCD timers, services/scheduled tasks — are reverted from their own menus (see Reverting changes). A System Restore Point (offered before moderate/heavy) rolls back everything at once.

Custom presets

You can define your own preset as a small text file and have the script apply it.

1. Create a folder named sincript_presets next to PerfTweaks.cmd.
2. Put a text file in it ending in .preset (e.g. mypreset.preset). A ready-to-edit example.preset ships with Sincript.
3. Run 10. Presets → 4. Custom preset, pick your file, review the summary, and confirm.

File format

• One directive per line, written as key=value.
• No spaces around the = (cleanup=1, not cleanup = 1).
• Start each directive in column 1 (no leading spaces).
• A line beginning with # or ; is a comment and is ignored.
• Inline comments are not supported — put comments on their own lines, not after a value.

Keys

Key	Value	Effect
cleanup	1	Cleanup core (temp/log cleanup, DNS flush)
privacy	1	Privacy/telemetry core
performance	1	Performance core (GameDVR off, game-task priorities, UI timings)
power	1	Power core (Ultimate/High plan, no sleep/disk timeouts)
network	1	Network core (TCP autotuning, RSS/RSC)
openasar	1	Install OpenAsar silently (bundled app.asar if present, otherwise downloads the latest nightly)
gamemode_off	1	Disable Windows Game Mode
gamebar_off	1	Disable Game Bar / Xbox Game Bar overlay leftovers (AppCaptureEnabled, Nexus, startup panel) — recording is already off in the performance core
edge_nudges_off	1	Edge policy: hide first-run experience, disable hubs sidebar and shopping assistant (does not uninstall Edge)
systemresponsiveness	0	SystemResponsiveness = 0 (favor foreground)
networkthrottling_off	1	Network throttling off (0xFFFFFFFF)
largesystemcache	1	Enable LargeSystemCache (situational; can hurt on desktops)
minprocstate5	1	Minimum processor state 5%
bcdtimers	1	BCD timer set (useplatformclock off, useplatformtick/disabledynamictick on, TSC enhanced)
ipv6_off	1	Disable IPv6 (DisabledComponents = 0xFF)
memcompress_off	1	Disable memory compression (raises RAM pressure on low-memory PCs)
nvme_flags	1	NVMe feature flags (may be blocked on fully-patched Windows)
gpu_telemetry_off	1	Disable GPU telemetry (NVIDIA tasks + opt-out; opt-out on AMD)
nagle_off	1	Disable Nagle on all interfaces (TcpAckFrequency / TCPNoDelay)
win32priority	42, 38, 26 or 2	Win32PrioritySeparation. 42 (0x2A) = short fixed quantum — the classic "42" tweak; because the quantum is fixed, Windows' Processor-Scheduling dialog reads it back as background services (that's what fixed means, not a bug). 38 (0x26) = short variable quantum, strong foreground boost — the exact value Windows' own Programs radio writes; the foreground app gets the longer slice. 26 (0x1A) = long fixed quantum. 2 = Windows default. 42 and 38 are opposite trade-offs (throughput vs foreground latency); pick to taste.
dns	cloudflare, google, or quad9	Set DNS on all active adapters

Keys not listed here (and 1-keys given any other value) are rejected.

What happens with a bad file

The script validates the whole file first and shows a summary: how many directives it recognized and how many problems it found, each listed (unknown key, or bad value … (expected …)). Then:

• Some valid, some bad → it reports the problems and asks whether to apply the valid ones anyway.
• Nothing valid → it aborts without changing anything and points you back to this key list.

Like the built-in presets, a custom preset writes a single JSON registry backup you can restore from the Backups menu.

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System tools

12. System tools holds general-purpose tools rather than tweaks. They change nothing on their own — you read first, then decide.

Edit PATH

Edits the System (HKLM, all users, needs Administrator) or User (HKCU, just you) PATH.

• Lists PATH as numbered entries and flags any folder that no longer exists as [missing] — the dead entries worth clearing out.
• Add a folder, remove one by number, drop all dead entries, or clean duplicates.
• It never uses setx. setx is documented to crop a value at 1024 characters — a real machine PATH is routinely longer, so it would silently destroy most of it — and to rewrite REG_EXPAND_SZ as REG_SZ, freezing %SystemRoot%-style references into literal paths. Sincript reads the raw value and writes it back as REG_EXPAND_SZ, so both the length and the %VAR% references survive.
• The whole Environment key is backed up to a .reg (via reg export, which is exact for REG_EXPAND_SZ) before any edit — and if that backup can't be written, the edit doesn't happen. A PATH you can't put back isn't worth the risk.
• After a change it broadcasts WM_SETTINGCHANGE, so new programs and shells see the new PATH without a sign-out. Programs already open keep the old value until they restart — expected, and the tool says so.

Editing the System PATH needs an elevated window. If you aren't elevated, sincript says so up front and offers the User PATH instead, rather than letting the save fail.

Find what is locking a file

Answers "what has this file open?" when Windows won't let you delete or replace something, using the Windows Restart Manager — the same API installers use.

• Give it a full file path; it lists every process holding the file (PID + name).
• Core Windows processes are marked [critical] using Windows' own classification, and sincript will not close them — a reboot is the only safe way to release a file they hold.
• Closing a holder is optional, one process at a time, and confirmed. It loses that program's unsaved work but does not delete the file; sincript then re-checks and tells you whether the file is actually free.
• No reboot and no extra downloads: openfiles needs a global flag and a reboot before it reports anything, and Sysinternals handle.exe would be an external dependency — so neither is used.

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Safety & backups

The script is built around being undoable.

• Per-value registry backups. Before changing any registry value, the script saves a small .reg file with only that one value's previous state to Documents\PerfTweaks_Backups (~1 KB each). Double-click it to put the value back. Values containing quotes or empty REG_SZ data are backed up in a form that restores correctly; filenames use a wide random suffix so two values under the same key can't overwrite each other's undo file in one pass. Re-applying a value already at the target (REG_DWORD or REG_SZ) is skipped, so a redundant apply can't overwrite its original backup. If the .reg backup cannot be written, the live registry write is refused.
• Full registry export (optional) — exports all of HKLM and HKCU to Documents\PerfTweaks_Backups. It verifies both exports actually produced a file before reporting success, so a failed or partial backup (not elevated, or the folder isn't writable) is flagged [ERROR] instead of a misleading [OK].
• System Restore Point (optional) — created on demand; Apply recommended safe set also offers to make one first.
• Log file — every action is logged to Documents\PerfTweaks_Backups\PerfTweaks_<random>.log as a clean [timestamp] EXEC / OK / FAIL timeline. It records each command's outcome, not its raw output, so it stays readable and doesn't fill with deleted-file paths or (on non-English Windows) garbled OEM-code-page error text.
• Honest status lines. Registry-heavy actions finish with [OK] only when every write succeeded; otherwise [WARN] with a count and inline [FAIL] lines pointing at what didn't apply (usually: not elevated, or a protected key). DNS, full-registry backup, OpenAsar, preset JSON restore, and admin-only repair actions (DISM/SFC, Windows Update reset, WinSxS compaction, memory compression, Store re-register) follow the same principle. The apply hosts and reset hosts actions refuse to overwrite the system hosts file until a backup has landed; restore can use the Documents hosts_*.bak if the local .bak is missing.

All backups and logs live in Documents\PerfTweaks_Backups inside your user Documents folder. The script auto-detects the real Documents path (including OneDrive-redirected Documents) and falls back to %USERPROFILE%\Documents if needed.

Reverting changes

Change	How to undo
Any single registry tweak	Double-click its .reg backup in Documents\PerfTweaks_Backups, or use Backups & status → Restore a single value backup (.reg)
CPU mitigations	Advanced → Enable mitigations
Boot (BCD) timers	Advanced → Revert BCD timers
DNS	Network → DNS → Automatic (DHCP)
Custom hosts	Apps & files → Restore hosts
Timer resolution	Apps & files → Remove timer resolution
Windows Game Mode	Settings → Gaming → Game Mode (or merge the value backup)
Game Bar / overlay residual	Merge the AppCaptureEnabled / GameBar value backups, or Settings → Gaming → Game Bar
Edge first-run / sidebar / shopping nudges	Merge the Edge policy .reg backups under Policies\Microsoft\Edge, or delete those policy values
Minimum processor state	Control Panel → power plan → set back to 100%
Removed built-in apps (debloat)	Reinstall from the Microsoft Store
Startup entry enabled/disabled	Flip it again under Apps & files → Manage startup programs, merge its .reg backup, or use Task Manager → Startup apps
Memory compression	PowerShell: Enable-MMAgent -MemoryCompression
A PATH edit	Double-click the PATH .reg backup written before the edit (in Documents\PerfTweaks_Backups)
SysMain / Superfetch	Merge its .reg backup, or sc config SysMain start= auto
Storage Sense / Delivery Optimization / CPU power throttling	Merge each one's .reg backup (they are policy values; the backup restores "not configured")
Windows AI (Copilot / Recall)	Merge their .reg backups, or restore the preset JSON backup
Telemetry firewall block	Elevated PowerShell: Set-NetFirewallRule -Group DiagTrack -Action Allow
Telemetry scheduled tasks	Task Scheduler → find the task → Enable, or PowerShell: Get-ScheduledTask -TaskName <name> | Enable-ScheduledTask
Registry values changed by a preset	Backups & status → Restore from a preset backup (JSON) (or run the relevant menu item to reverse it)
Everything at once	Roll back to the System Restore Point, or import the full registry backup

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Optional bundled files

Some actions can use files placed next to PerfTweaks.cmd. They are optional:

• app.asar — an OpenAsar build for the Discord action. If absent, the script offers to download the latest nightly from the official OpenAsar GitHub releases (https://github.com/GooseMod/OpenAsar).
• boot.config — a Unity engine boot configuration applied to a game's *_Data folder.
• hosts — an ad/telemetry blocklist that the "apply hosts" action installs (the original is backed up first).
• SetTimerResolution.exe — the timer-resolution helper from valleyofdoom/TimerResolution. Apps & files → Apply timer resolution copies it to C:\ProgramData\Sincript, registers a hidden logon task that holds your chosen resolution, and (on Windows 10 2004+/11) sets the registry switch that makes the change system-wide.

SteamLight needs no bundled file. Apps & files → Install SteamLight finds your Steam folder via the registry, writes a SteamLight.bat launcher into that folder, and adds a SteamLight Desktop shortcut. The launcher starts Steam with resource-saving flags (single process / single core, no shaders, no shared textures, no Big Picture, high-DPI off, etc.) for lower RAM/CPU use. It references steam.exe relative to its own folder, so it keeps working even if Steam is on another drive. To change the flags, edit the single _SLFLAGS= line.

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Recent changes

Newest first. Feature details live in the sections above — this is just what changed.

• Win11 quiet surface + Game Bar residual. Privacy core now also quiets the remaining Start/lock Content Delivery tips, search-box suggestions, and tailored experiences (still reversible via :SafeRegAdd). Performance optionally disables Game Bar / Xbox overlay chrome (AppCaptureEnabled, Nexus, startup panel) without uninstalling Xbox — recording stays off in the performance core. Privacy optionally applies documented Edge policies (hide first-run, hubs sidebar off, shopping assistant off). Custom preset keys: gamebar_off=1, edge_nudges_off=1. Guarded by tests 69–71.
• Reliability pass (backup / restore / honesty). Registry writes now refuse to proceed if the per-value .reg (or preset JSON temp) did not land — the same bargain PATH and hosts apply already had. Idempotent skip covers REG_SZ as well as DWORD, so a re-apply cannot bury the true-original undo. Hosts reset aborts without a landed hosts.bak; hosts restore falls back to Documents hosts_*.bak when the local .bak is missing. Presets abort if the JSON temp cannot be created. Timer-resolution install reports via :Summary / _FAILS; Store re-register is elevation-gated with an exit-code check. SteamLight verifies the Desktop .lnk before claiming it; memory-compression disable no longer swallows failures (preset path bumps _FAILS); NVIDIA telemetry tasks are found by name prefix (NvTmRep_ / NvTmMon_ / NvDriverUpdateCheckDaily_) instead of hardcoded GUID \TN paths. Guarded by tests 60–68 (plus Store on test 28). Static harness is now 71 checks.
• VerboseStatus (optional): Added an opt-in boot/logon diagnostic tweak (verbosestatus=1) with honest reporting explaining when DisableStatusMessages suppresses it. Guarded by test 59.
• Disable Widgets / News & Interests, and Windows Spotlight on the lock screen: Included in the Privacy Core, and presets. Guarded by test 59.
• Fixed: parentheses in a status message crashed the tool (mitigations). :Summary printed its message inside a one-line if ( ) else ( ) block, so the first ) in the text — e.g. the mitigations line's (incl. Downfall/GDS), or an empty () — closed the block early and aborted the script ("was unexpected at this time"). :Summary is now written with goto branching so the message is never inside ( ); any caller text is safe. Guarded by test 58, which fails if the routine is ever put back into a parenthesised block.
• System tools (menu 12). New PATH editor — System or User, lists entries, flags dead ones, add / remove-by-number / drop-dead / de-duplicate — and find what is locking a file (Restart Manager: lists every holder, marks critical Windows processes and refuses to close them, optional confirmed per-process close, checks for parens in paths). The PATH editor never uses setx (it crops at 1024 characters and freezes %SystemRoot% into literal paths), backs up the whole value first, and broadcasts the change so new programs see it without a sign-out. Guarded by tests 31–42, 55.
• Privacy: Windows AI off by policy. Copilot (user and machine policy), Recall (enablement blocked, snapshot saving off, data analysis off), Click to Do, plus inking/typing personalization and online speech recognition. It rides along everywhere privacy is applied — menu 3, Apply recommended, and every preset — through the same backed-up, reversible path. The Privacy screen now also states two things it previously implied away: AllowTelemetry=0 is only honored on Enterprise/Education (Home and Pro clamp it to Basic, 1), and stopping DiagTrack also stops Xbox achievement sync and the Feedback Hub. Guarded by tests 43–46.
• More optional knobs. Performance: Storage Sense off · Windows Search classic scope · SysMain/Superfetch off, which first probes the Windows disk and warns before the prompt if it looks like a mechanical HDD. Power: CPU power throttling off. Network: Delivery Optimization off. Privacy: four more telemetry scheduled tasks — looked up by name and reported as found vs disabled instead of a blind "done" — plus an optional firewall block for the telemetry service that flips Windows' own DiagTrack rules. Guarded by tests 47–50.
• Three popular tweaks verified against Microsoft's documentation and declined — regrouping svchost (SvcHostSplitThresholdInKB), lowering ServicesPipeTimeout, and disabling the prefetcher. They are listed with their reasons on What was excluded, and test 51 fails if any of them is ever quietly added back.
• Elevation works when the script path contains an apostrophe (e.g. C:\Users\O'Brien\) — the UAC relaunch now passes %~f0 via $env:PT_SELF instead of embedding it in Start-Process -FilePath '…', where a ' broke the string and killed the relaunch with no prompt. Guarded by test 26 (with SteamLight's PT_SLDIR hand-off).
• Per-value backups decline non-ASCII string data instead of corrupting it. Undo files are written with echo (console code page), so non-ASCII REG_SZ prior data came back as mojibake; such values are now marked not auto-restorable — use the full backup (like REG_BINARY) and skipped on preset restore. The full reg export still restores them correctly.
• Safe defaults on confirmation prompts. Each (Y/N) gate clears its variable first, so a bare Enter = skip rather than a stale Y (restore-point prompts default to Yes). This stops the irreversible clear-all-Event-Viewer-logs step firing from a stray Enter.
• Cleaner log file. :Run logs only [timestamp] EXEC / OK / FAIL, not raw command output (which dumped file paths and garbled OEM-code-page errors on non-English Windows). Outcomes are still recorded.
• SteamLight reports honestly. [OK] is gated on the launcher .bat actually being written, so an unwritable Steam folder (e.g. under Program Files without elevation) yields [ERROR] instead of false success.
• Honest registry-action reporting. Registry-heavy actions/presets track a failure tally, print inline [FAIL], and finish via :Summary with [OK]/[WARN]; :Run counts failure only when genuinely not elevated. Guarded by tests 13–15, 24–25, 27.
• Limited mode when UAC is declined. On failed elevation the script sets a not-elevated flag, explains HKLM/service/boot changes won't work, and asks to continue per-user-only; repair actions gate their final line on elevation. Guarded by tests 17, 28.
• Preset parser empty-value guard. A key= line with no value no longer aborts the script. Guarded by test 16.
• hosts apply requires a backup first — confirmed landed before overwriting the system hosts. Guarded by test 18.
• Preset JSON restore honesty + quote-safe REG_SZ. [WARN]/[ERROR] on partial/unreadable backups; REG_SZ restores via Set-ItemProperty so quotes survive. Guarded by tests 19, 23.
• OpenAsar targets the newest Discord build by version, not folder-name order (which could pick an older build after a digit rollover). Guarded by test 20.
• Per-value backup integrity. Quotes in prior REG_SZ data are escaped, empty values handled, and filenames use %RANDOM%%RANDOM% so two values under one key can't collide. Guarded by tests 21–22.
• Startup programs manager (Apps & files). New Manage startup programs item lists the Run keys (HKCU, HKLM, HKLM-WOW64) and both Startup folders and flips entries Enabled/Disabled via the reversible StartupApproved switch Task Manager uses. Nothing is deleted; each flip saves prior state to a tiny UTF-16 .reg backup (so non-ASCII names restore), and one PowerShell worker with a fixed sort order flips localized (e.g. Cyrillic) names exactly. Guarded by test 12.
• Fixed: restoring/resetting the hosts file crashed the script. An unescaped ) in (AV tamper protection?) inside a one-line if ( ) else ( ) ended the block early and aborted the batch ("was unexpected at this time") after the file was already written. The parens are escaped and test 9 (cmd block-parse simulation) now catches any unescaped ) in a block.
• Fixed: the Ultimate power plan never activated, and clones piled up. powercfg -duplicatescheme with no destination GUID minted a random-GUID copy each run while /setactive targeted the canonical GUID, so the High Performance fallback activated and a clone accrued per power-core run. Duplication now targets the canonical GUID itself. Guarded by test 10.
• Fixed: a failed OpenAsar download could install a broken file. Invoke-WebRequest can leave a partial file, and both paths only checked existence; they now trust the child exit code and delete the leftover first. Guarded by test 11.
• No more false "success" messages (first wave). The full registry backup confirms both HKLM and HKCU exports wrote a file (else [ERROR]); DNS apply/reset counts adapters changed vs failed (e.g. 3 adapter(s), 0 failed); OpenAsar reports which backup was saved, since AV / Controlled Folder Access often blocks the copy into Discord's own folder.
• Performance: a Win32PrioritySeparation choice — 1 = 42 (0x2A, short fixed quantum — the classic tweak; the Windows dialog will show background services, because a fixed quantum treats all apps equally), 2 = 38 (0x26, short variable quantum — the value Windows' Programs radio writes, foreground gets the longer slice), 3 = 2 (Windows default — undoes a previous 42 or 38), N = unchanged. One mutually-exclusive prompt, so its single-value .reg backup captures the true prior value rather than one just written.
• Prefetch is no longer cleared — it's placebo (Windows rebuilds it) and against the script's own stance; removed from cleanup/recommended/presets and listed on What was excluded.
• Backup-folder manager (Backups & status). New Manage / open backup folder item summarizes Documents\PerfTweaks_Backups by category (counts + MB), opens it in Explorer, and offers a safe prune of older full-registry exports while keeping the newest pair. The small .reg and preset-JSON undo data is never deleted.
• In-app single-value restore (Backups & status). New Restore a single value backup (.reg) item lists per-value .reg backups (newest first) and re-imports your pick, logged; full-registry exports (FullReg_*.reg) are filtered out. The preset-JSON restore is unchanged.
• Per-app CPU priority (Advanced). New Set permanent process priority pins a per-.exe priority (High / Above normal / Normal / Below normal / Low) via Image File Execution Options (CpuPriorityClass), reversible with Remove override. Target the .exe that actually runs (Task Manager → Details); Realtime isn't offered.
• Reversibility + WinUtil tweaks. Nagle and the per-user sync-services disable are now backed up, and the status helper is hardened against a > in registry data. Added opt-in items: mouse acceleration off, show file extensions, and Activity History off (PublishUserActivities / UploadUserActivities).
• GPU hardware scheduling (HAGS). New Advanced toggle for HwSchMode (reversible; needs a reboot and Windows 10 2004+ with a supporting GPU). Kept out of presets because turning it off disables features like NVIDIA DLSS 3 Frame Generation.
• AMD telemetry opt-out. The GPU-telemetry action and gpu_telemetry_off key now also opt out of the AMD User Experience Program (backed up), pointing to AMD Software → Preferences. Previously a no-op on AMD.
• Status screen + localization. Adds hibernation, minimum processor state, HAGS and memory compression (read-only), and — with DNS apply/reset — no longer depends on English output: it reads registry/cmdlet properties, filters TCP via netsh on the : separator (dodging Get-NetTCPSetting where MSFT_NetTCPSetting is missing), and applies DNS to all physical adapters. Works on Cyrillic Windows.
• Presets, custom presets & JSON backups. New 10. Presets menu (light / moderate / heavy + custom .preset files), each writing one restorable JSON backup; What was excluded moved to item 11.
• Console-font fix. The last two inline-PowerShell spots (Unity core detection, boot.config rewrite) use the minimized-window pattern; boot.config paths pass via environment variables.
• Community-guide tweaks. BCD timers also set useplatformtick yes; optional minimum processor state 5%; optional Game Mode off; a debloat action (apps reinstallable from the Store).
• Timer resolution. SetTimerResolution installs as a hidden logon task plus a system-wide registry switch (needs a reboot); fully removable.
• Backups moved to Documents (Documents\PerfTweaks_Backups, OneDrive-aware) instead of the drive root.
• Console compatibility (Windows 10 / Server 2022). ASCII-only / no BOM, echo-off guard, working-directory fix, suppressed mode/color errors, ASCII logo — so @echo off and the menu render on legacy cmd.exe.
• Unity boot.config is CPU-aware — sets job-worker-count / -maximum-count to logical processors − 1 before copying into the game's *_Data folder.
• Bundled-file error handling. Missing/empty boot.config or hosts, and copy failures, now stop with a clear message.

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Troubleshooting

Newest issues first — most are about elevation or reboots, because that's where Windows quietly ignores a change that the script did make.

• A tweak "did nothing" until I rebooted. Expected for several of them — CPU mitigations, memory compression, NVMe flags, boot timers, timer resolution. The registry value is written immediately; Windows only acts on it at boot. Reboot, then re-check.
• A privileged change shows [WARN] / a [FAIL] line. The window isn't elevated, or the key is protected. Close it, relaunch, approve the UAC prompt. [WARN] in limited mode is honest reporting, not a failure of the script.
• AllowTelemetry=0 didn't stick / telemetry still runs. On Home and Pro, Windows clamps AllowTelemetry to Basic (1) — only Enterprise/Education honor 0. The script says so on the Privacy screen; this is Windows, not a bug.
• Disable CPU mitigations, but another tool still flags Downfall/GDS. Make sure you're on the current build — the combined value is 0x2000003 (it used to be 3, which left Downfall mitigated). Then reboot and re-check with Get-SpeculationControlSettings in PowerShell; the mitigation change only applies at boot.
• Processor-scheduling dialog shows "background services" after option 1 (42). Not a bug: 42 is a fixed quantum, and a fixed quantum treats all apps equally, which is exactly what that radio reports. If you want the foreground-favouring value, pick option 2 (38) — the same value Windows' own Programs radio writes.
• A backup didn't restore a value cleanly. Non-ASCII REG_SZ data and REG_BINARY are marked not auto-restorable — use the full backup; the small per-value .reg undo can't carry them, but the full reg export restores them correctly.
• Backups aren't in my Documents. They're written under whichever account is elevated. If you elevated with a different admin account, they're in that account's Documents.
• A short black window flickers during DNS / OpenAsar / restore-point / status. That's a deliberately minimized, short-lived PowerShell window so the main console's font/colors aren't disturbed. Normal.

Notes & caveats

• Run as administrator. HKLM changes, services, scheduled tasks, BCD edits, and restore points all need elevation. The script elevates itself; approve UAC for the full toolset. In limited mode after declining UAC, expect [WARN] on privileged actions — intentional honesty, not a bug.
• Backups go to your Documents. They're written under the account that is elevated. On a normal single-admin PC (UAC consent prompt) that's your own Documents; if you elevate with a different administrator account, they land in that account's Documents instead.
• A reboot is recommended after several tweaks (memory compression, mitigations, NVMe flags, boot timers, timer resolution) for them to fully take effect.
• Brief minimized windows. Some actions (DNS, Store re-register, OpenAsar download, restore point, the status screen) run PowerShell in a short-lived minimized window so the main window's font/colors aren't disturbed. The flicker is normal.
• The "Advanced" menu is genuinely advanced. A few highlights:
  • Disable CPU mitigations trades security hardening for speed. It disables the Spectre/Meltdown/MDS/SSBD/L1TF set (FeatureSettingsOverride bits 0-1) and Downfall/GDS (bit 25, 0x2000000, per Microsoft KB5029778) in one step — the combined value is 0x2000003 (decimal 33554435), with the override mask widened to match so every bit is actually honoured. Only do this where you understand and accept the exposure; a reboot is required, and Enable mitigations reverses all of it.
  • NVMe feature flags may be blocked by Microsoft on fully-patched systems; the script tells you so.
  • Disable memory compression frees a little CPU but increases RAM pressure on low-memory PCs.
• Opt-in only. Riskier items such as disabling mitigations and enabling LargeSystemCache are never part of the "recommended safe set" — you must select them yourself.
• Console appearance. The script uses a magenta theme and a small "SIN" logo. It runs in your default console font (Consolas on most systems) and changes no system-wide console, scaling, or registry settings beyond the tweaks you choose.

"What was excluded" — the philosophy

The in-app 11. What was excluded screen lists, by category, the popular "tweaks" this script intentionally omits — for example security-weakening changes (disabling Defender, the firewall, UAC, or SmartScreen), placebo or obsolete registry values, clearing the Prefetch folder (Windows just rebuilds it, slowing the next few launches), firewall rules that block Google/YouTube IP ranges, hard-coded MTU values, and bulk undocumented GPU dumps. It also covers items from popular gaming guides that are deliberately skipped — Windows activation scripts, replacing Defender with a third-party antivirus, aggressive RAM / standby "cleaners", and forcing MSI mode or NIC parameter edits (which the experienced guides themselves advise against). Read it to understand the safety rationale.

Three tweaks other optimizers ship were checked against Microsoft's own documentation and left out on the evidence:

• Regrouping svchost services (SvcHostSplitThresholdInKB). Windows splits services into separate processes above 3.5 GB of RAM on purpose: Microsoft documents the benefits as reliability, inter-service isolation, per-service resource management and clearer diagnostics — and describes the footprint saving from regrouping as modest. Isolation is worth more than the RAM, so this sits under security-weakening alongside VBS/HVCI.
• Lowering ServicesPipeTimeout to 30000. 30 seconds already is the Service Control Manager's default, so the write changes nothing — and 60000 is the well-known fix people apply when a service legitimately needs longer to start, so applying this would silently undo it.
• Disabling the prefetcher (EnablePrefetcher=0). The same cost as clearing the Prefetch folder — which this script already declines, because the next launches just get slower — only permanent, and for close to nothing on an SSD. SysMain on/off is offered separately, under Performance.

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Tests

Sincript ships with a static-analysis harness in tests/. PerfTweaks.cmd is interactive and changes the system, so it can't be safely unit-tested by running it; instead tests/Run-Tests.ps1 (71 checks on stock Windows PowerShell 5.1 — no Pester) parses the script text for invariants that tend to break silently, including:

• every menu goto / call resolves to a real label
• no unescaped ) inside a ( ) block (cmd parser simulation — that class of bug crashed the hosts restore)
• no duplicate boot.config keys; example.preset keys match the in-script validator
• honest reporting (:Summary, _FAILS, elevation gating, DNS/OpenAsar/backup guards) does not regress
• backup undo integrity (quote escaping, collision-resistant filenames, hosts backup-before-overwrite)
• the PATH editor never invokes setx, keeps REG_EXPAND_SZ, and backs up before writing
• the lock finder refuses to close processes Windows marks critical
• advisories (laptop, desktop, disk) stay warning-only and appear before their prompt
• the tweaks listed on What was excluded are never quietly written back
• every cleanup delete is gated on a proven root, so an unset variable can never collapse "%TEMP%\*.*" into "\*.*"
• Win11 quiet-surface keys stay in privacy core; Game Bar residual and Edge nudges stay opt-in (not folded into performance/privacy cores)

Run from the repository root:

powershell -NoProfile -ExecutionPolicy Bypass -File tests\Run-Tests.ps1

Exit code 0 means all 71 checks passed; 1 means at least one failed, with the offending detail printed. See tests/tests_README.md for the full numbered list.

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Disclaimer

Use at your own risk. These tweaks modify system settings; while the script backs up each change and can create a restore point, you are responsible for your system. Make a restore point and/or a full registry backup first (the script provides both). Sincript is an independent utility and is not affiliated with or endorsed by Microsoft, NVIDIA, AMD, Discord, or any other vendor mentioned.