How to create shortcut to start program with specific affinity settings. (All 32 cores)

I found a lot of instructions on how do do this but none actually work.

I'm trying to start a game and set it to use all cores. The reason is the game (Assassin's Creed Odyssey) crashes on the newer CPU's. If I manually tell it to use all cores after the proccess is started it's stops crashing.

At least it no longer crashes in the short window it usually does, I haven't tested it for more then 5 minutes or so. It ran beautifully on our old i7-4790K.

This is what I have at the moment. A shortcut with this in the target box. It does start the game.


I have an i9-14900K, it shows 32 cores. CPU0-CPU31. I typed 32 1's into a binary to hex converter and got FFFFFFFF.

In the shorcut I tried changing the priority, that part works, but the affinity never changes.

i9-14900K has 8 performance and 16 efficiency cores (not threads). You don't want the E-cores running your game.

best process inspection tool for P/E cores on windows 11?
Which cores are the E-cores and which are the P-cores? How does Windows choose to distribute the load across the 24 threads?

8 P-cores = FF

A lot of Reddit gamers report good results using Process Lasso.

garlin said:

i9-14900K has 8 performance and 16 efficiency cores (not threads). You don't want the E-cores running your game.

best process inspection tool for P/E cores on windows 11?
Which cores are the E-cores and which are the P-cores? How does Windows choose to distribute the load across the 24 threads?

8 P-cores = FF

A lot of Reddit gamers report good results using Process Lasso.

Click to expand...

#1 If I create a shortcut with the following target, it still does not have any effect on the proccess' affinity.


#2

The proccess always starts with 0-15 selected. If I leave it this way it crashes at random times within the first few minutes.

I tried manually changing it to 0-7 just after the proccess opened and the game get stuck on the splash screen.

If I manually changes it to all cores just after the proccess opens, the game doesn't crash (I still need to test run it longer then 5 minutes this way)

I'm not trying to increase performance of something that is working right, I'm trying to put a band-aid on something that is not.

Note: I checked a few other games, they all use all cores by default.

OK, I found this script on Reddit:
Processor Affinity set script - Fix freezing with intel cpu after alder lake

Shrunk to one line.

garlin said:

OK, I found this script on Reddit:
Processor Affinity set script - Fix freezing with intel cpu after alder lake

Shrunk to one line.

Code:

powershell -WindowStyle hidden -noLogo -nop -C "Start-Process 'G:\Games\Assassin's Creed - Odyssey\ACOdyssey.exe'; Start-Sleep 25; (Get-Process ACOdyssey).ProcessorAffinity = (1 -shl (Get-CimInstance Win32_ComputerSystem).NumberOfLogicalProcessors) - 1"

Click to expand...

Awsome find, thank you. I'll try it out and report back if it does what it's supposed to but .... The game just crashed after 7 minutes running on all cores.

If it does set affinty then you've answered the question relevant to this forum.

The game doesn't freeze though, it's just an instant CTD with no entry the event log.


Note: It's just this one game. I've tried a lot of things, different refresh rates, screen modes, different v-sync and frame limiter settings, in game and in the nvidia control panel. So far nothing has changed the crashing. I may just have to wait and see if GOG releases a working version