Testing Undervolt Stability - iGPU usage lowers CPU clock

[Ginger Penguin]

Hi all,

 

I'm trying to undervolt my 10750H and I'm getting good results so far but I've been using Prime95 to stress the CPU and Furmark to stress the integrated graphics at the same time to make sure the component is pulling the max amount of power to test the stability. The problem is after a while, the clock speed tanks to anywhere from 3.2GHz-3.8GHz. If I stop Furmark, it'll rise up again to 4.17GHz which appears to be its max all-core. I'm worried that it lowering the clock speed of the CPU means I'm not getting an accurate reading of its stability.

 

Any thoughts? Cheers!

[SkilledRebuilds]

36 minutes ago, W.D. Stevens said:

Hi all,

 

I'm trying to undervolt my 10750H and I'm getting good results so far but I've been using Prime95 to stress the CPU and Furmark to stress the integrated graphics at the same time to make sure the component is pulling the max amount of power to test the stability. The problem is after a while, the clock speed tanks to anywhere from 3.2GHz-3.8GHz. If I stop Furmark, it'll rise up again to 4.17GHz which appears to be its max all-core. I'm worried that it lowering the clock speed of the CPU means I'm not getting an accurate reading of its stability.

 

Any thoughts? Cheers!

Try the same withour Furmark but with something different.
Then you can have 2 sets of data to work with.

[Ginger Penguin]

Good idea. I'll try that. Though I just did a run with just Prime95 and after a period of time, the clock speeds did drop so I'm not sure exactly what the issue is. It still does it with no undervolt and it doesn't seem to be a result of thermal throttling because according to HWinfo, 2-4 cores thermal throttle pretty quickly but it still hovers between 4-4.1GHz then drops down to the high 3s at some point later after it's already been at the thermal limit for a while.

[Kilrah]

It's just the power limits, which are typically locked on mobile platforms. PL2 is usually allowed for 20 seconds or so, then it goes back to PL1.

 

https://www.gamersnexus.net/guides/3389-intel-tdp-investigation-9900k-violating-turbo-duration-z390#:~:text=Intel allows for up to,for the limited duration permitted.