VCACHE-TRAY

A tray utility to control dynamic CCD preference of heterogeneous AMD 3D V-Cache CPUs like 7950x3D and 7900x3D. Some privileged games (aka. GenSh1t ) and programs are refused to set affinity, this utility may help to overcome this case to schedule these bad behaved programs to preferred CCD without locking preferred CCD in BIOS.

Requirements

• Recommended installing latest BIOS and AMD chipset driver.
  • At least BIOS and drivers which support 7000x3D CPUs.
• Option CPPC Dynamic Preferred Cores in BIOS menu AMD CBS/SMU must be set to AUTO or Driver to allow OS to control via AMD 3D V-Cache Performance Optimizer device
  • Otherwise this device will not work and appear in Device Manager.
• Recommend turning off Game Mode and xbox Game Bar in Windows, since you are gonna use this utility to control CCD preferences and profiles manually.

Note

• ⚠ On ASUS ProArt-x670E, BIOS 1202, if Max Clock Limit is enabled in PBO menu, both BIOS and driver CPPC prefer CCD function will not work properly, dunno why.
• ⚠ Recommended switch prefer CCD or setup profile before starting new program, it looks like some activated threads will stick on original CCD until they are terminated.
• ⚠ Prefer CCD may not affect programs or threads that have been set affinity by themselves, manually or other process management software like ProcessLasso.
• ⚠ Reset Service Forcefully option may cause buggy AMD 3dvcache or system stuck, use with caution!
  • Restart Service on Apply is NOT recommended, just wait for 3dvcache polling the registry changes, although this may take a while sometimes.

How to use

Run it and switch modes via tray icon.

To start with Windows, create a task in Task Scheduler.

Pass -h to check more options, --alloc_console to show debug logs.

How does it work

While I was investigating 3D V-Cache driver and planning to take over control of device, but I found that AMD put a registry interface HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\amd3dvcache\Preferences to allow change things on the fly. It will take a while, like, up to several minutes to take effect without restarting the 3dvcache service. That's it, this program is just a simple frontend of these registry interfaces.

Tweaks

This utility also provides some simple tweaks to ZEN4.

Tweaks can be disabled completely via config json or argument --no_tweaks.

Tweaks will be applied again after S3/S4 resume.

• Package C6: recommended disabling it to reduce freeze/shutter in gaming
• Core C1E: recommended disabling it to reduce freeze/shutter in gaming
  • disabled by default, enable it will cause CPU package power display differently in HWinfo
• Core C6: recommended disabling it to reduce freeze/shutter in gaming
  • disabled by default if Meidum Load Boostit enabled in BIOS
  • boost freq may be limited if multiple cores are activated at the same time without Core C6 enabled, this may behave differently on various BIOS/CPU, please check on your platform.
• No C-state Timers: some c-state features and timers will be disabled, with this tweak, it looks like tiny freezes/shutters in some games are eliminated
  • for more details, please check source code for what this tweak does
• CPB: something like TurboBoost on blue brand
• Perf Bias: some perf bias tweaks collected from Web and BIOS, may help in some specified workloads
  • Default: will not touch anything
  • These tweaks write some undocumented MSRs, not sure what they control, some of those MSRs control something critical like op-cache, which can have a performance impact in some workloads

Build

Build with msys2 and cmake.