Dear AMD and other forum users,

I have recently build a nice new APU ITX rig. The components I have used are the following:

AMD A10 5800K

ASRock FM2A75M-ITX (bios 1.20 and 1.50)

Kingston 2x4GB 1866Mhz CL 9 (KHX1866C9D3K2/8GX)

Be Quiet L7 300watt

Windows 8 Pro 64bit (latest drives installed)

Crucial M4 128GB

The problem I have is when the CPU and GPU part of the APU are 100% stressed the CPU clocks back to 1.4ghz. Max load temperature is 50 degress celcius and idle is 28. This problem does not occur when I only stress the CPU to 100%. Or when the GPU load is below 100%. I can replicate this by using Prime95 and Furmark. I first discovered the problem because of sudden FPS drops in games.

I have already tried disabling all power saving features and temperature protection in the bios and setting the APU to fixed clock rates and voltages. Unfortunatly this has no effect.

I suppose the problem is either in the APU or in the motherboard. The motherboard only uses a 4pin CPU connector, is this to little for the AMD A10 to run GPU and CPU on full speed?

Hopefully I will be able to solve this issue with your help!

Have you solved this issue yet?

If not, I may be able to help!

No I haven't solved it yet, but the problem is known however.

Apperently the VRM's on my motherboard are getting too hot which causes overheating protection to kick in and lower de CPU clock. I am sending my motherboard back and hope te get a better replacement.

This is a (now) known issue with the ASRock FM2A75M-ITX.