CPU Usage in games

[nemiroN]

Hi. My setup is laptop Asus Tuf Gaming A15 FA507XU with Ryzen 9 7940HS and RTX4050.  I have a question about CPU usage in games. For example in Counter-Strike 2 in optimus(hybrid) mode when igpu and gpu is both used my cpu TDP and Clocks is much lower than in dgpu only mode, but perfomance in games is same. So CPU is kinda wasting power or what? In benchmarks in hybrid mode it easily can boost up to 5.2ghz and 80w tdp but in games it usually sits on 4.7ghz and 20-25w. in dgpu mode it sits on 5-5.2ghz and 30-40w. TDP value for igpu and cpu is the same (CPU power package)

[ElectroStingz]

Hello,

There is a power share feature so depending on the mode there can be more available for the CPU / GPU which will impact the boost clock feature. But performance also depends on other factors, like if the game doesn't need a powerful CPU to run or if other limitations exist, (GPU limit), you could have 5GHz vs 4GHz CPU and see no difference in fps due to the RTX 4050.

You would need to use a game that is heavier on the CPU to determine if there is a significant difference but also whilst there may be an FPS limit, higher CPU clocks may be noticeable when you look at min, max and sustained FPS. (Try cyberpunk benchmark if you have it)

[nemiroN]

Hello. I have tested cyberpunk in gpu and cpu bounded scenarios and results is the same. But in dgpu mode cpu is wasting more power and raising temps for nothing
https://youtu.be/Cmt58-yOqsc

[ElectroStingz]

From watching you can see the FPS peaks higher on dGPU only ultra and your result at the end shows this too with the peak (max fps), tiny performance gain.

But anyway, your question, is it worth the extra boost for the increase in temps and small performance gain? I think lower temperatures are always going to be a better choice over a small unnoticeable fps increase. By allowing the CPU to have more power what you are seeing is normal operation, boost clocks always cause a higher Vcore and that is your main heat source.

[nemiroN]

Yes, but i`m intererested what causes this behavior? i`m understand the reason is that igpu is enabled or enabled. I found some videos on youtube comparing game perfomance with optimus or dgpu mode but all of them had similar cpu usage. But in my case cpu is wasting power

[ElectroStingz]

It's the CPU boost clock and Vcore increase, when you have the igpu disabled the CPU has more power to use for the boost clock.

If you got a higher FPS in cyberpunk benchmark, is it wasting power? 🙂

[nemiroN]

Extra +20w does not worth 1-3% perfomance increase. Also i play games only with locked fps, and even with locked fps cpu overboosting for nothing. obviously, this is strange but thank you for reply 

[ElectroStingz]

This might help you understand why.

https://hexus.net/tech/news/cpu/121130-amd-shares-precision-boost-overdrive-explainer-video/