Well, I sometime back got a new computer which has a lot of cores (20 I think, I know big smiley face!). But what I have noticed is that I run into issues with some programs/games which are not expecting the multiple cores or were not built very well. One example recently is Strider (2014) - a good metroidvania by the way - which refused to start, nothing at all, just nothing happened. After looking into it, it was down to it not liking multiple cores and the solution was this:

in Start Menu serach type "msconfig"
Under Boot tab, select Advanced Options
In here the Number of processors check box and the number below it sets how many processors windows boots with.
If you check the box, and select a low amount, e.g. 4 or 8 and then click ok and ok again, Windows will reboot and run with the sepcified number of processors (and Strider then runs fine).
Remember to set this back to unchecked in msconfig after use otherwise you are not using all cores.

This tip has been useful in various scenarios, so thought I would share it with you.

No idea. For strider no process is created, it simply does nothing. Just sharing what I use that I know works.

Intel Core 12600 or higher, I presume.

Running on Windows 11 should fix your problems. I hear there is some lasso tool you can use to programmes to use desired type of core (P/E aka power/efficiency aka big/little) but I guess you need the latest UEFI and drivrers for that. Cannot say much as I have not even seen the processor family nor W11 in real life yet.

Some programmes will just not run on E cores as they are lacking exstensions.

According to PCGW, it does not like more than 8 cores.

Ah, right, I forgot some games are like that. Like howe Fallout 3 disliked more than 2 cores at the time. The same fix (but limiting to 6 or 8 cores instead of just 2) might work then.

Should always check PC Gaming Wiki. That is what it was made for. I should do as I say.

Have you tried to deactivate some cores in the UEFI/BIOS? That shpuld solve your problem.

I remember trying Nier Automata some years ago, and it would crash. But when i changed the affinity to 2 cores as suggested as a workaround, the game worked fine! Beautifully in fact. Though i used a task manager that would remember settings so once i did it, it wouldn't do it again.

Though for single-thread programs it wouldn't make a difference. It would come down more to ones that try to make more threads and has too many, or more likely had a fixed number of slots for how many cores they expected and the rest is the result of buffer overrunning... Though i'm sure there's 3-4 actual uses (1 for graphics, 1 for controller input and loading files, 1 for music/sound effects, etc. Using more than that it would have to be pretty intensive on AI/Graphics...)

Hi, sorry guys, must be a misunderstanding here. This isn’t a thread asking for help. I had some issues with some products, and the solution was what I presented in my first post. Just sharing the information in case anyone else had these issues :o)

Your solution worked but maybe not the most elegant one, that's why I guess people are giving you other options.
In my case I would imediately go to BIOS, disable some cores and test. If works, then set the core affinity permanently with Process Lasso, this way you don't need to reboot to play the game and everything works flawlessly.

Regarding Process Lasso, it's an awsome tool and if properly set, some affinity brings quite a good increase in performance in some games. I made a post some time ago with some numbers on old Core2quad CPU's.

Edit: can't seem to find that post but I recall on some older games like Richard Burns Rally getting ~25% more fps by setting the affinity to 2 instead of 4 cores.
I also recall playing with affinity and compatibility setting to solve some bugs and performance issues on older games, like Populous the beginning. If memory serves, running the game on Windows XP compat. setting with 2 cores only give the best performance.

There is also the option to use shortcuts or scripts to set CPU Affinity and Priority in Windows 10/11.

For programs with one process you can use shortcuts:
https://www.windowsdigitals.com/how-to-set-process-cpu-affinity-priority-permanently-in-windows-10/

For programs with multiple processes (Chrome, Firefox, etc.) you can use scripts:
https://www.windowsdigitals.com/auto-set-priority-and-affinity-in-windows-11-10/