Fatal1ty X370 Gaming X / AB350M Pro4 too hot APU

Update topic.

Ivan_83 wrote: I have Bristol Ridge 9700 and X370 Taichi Fatal1ty X370 Gaming X AB350M Pro4 Then I use taichi CPU temp 27-40C and it agressive changes: fast up and fast down. On other MoBos CPU temp 39-55C. I want disable video adapter because I use PCI-E video card.

I'm not sure I understand your question.

You say your 9700 CPUs are hotter on the Fatal1ty X370 Gaming X and AB350M Pro4, because those boards can use the AMD iGPU, while the X370 Taichi cannot use the iGPU. Is that right?

But on ALL of these boards, you are using PCIe video cards, is that right?

Since you only use video cards, you want to disable the AMD iGPU on the other two boards?

In the Chipset Configuration screen, where you select video card or iGPU, do you have an option called iGPU Multi-Monitor, or something similar to that?

If you do, set that option to Disabled. That is the option used on Intel mother boards, to disable the iGPU in Intel CPUs.

But, the iGPU in any CPU normally cannot have its power set to off, so it always is using a little power and will create a little more heat.

To compare CPU temperature between the three boards, all the main parts in each PC must be the same, same video card, same PC case and chassis fans and number of fans, same CPU cooler, same VCore and CPU speed.