Low clock speed when at 100% CPU load

TahoeJones

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Mar 29, 2011
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I am running an A10-6800k (4.1GHz) on a ASRock Extreme6+, which has been running Prime95 for the past four hours. I am using HWiNFO64 and HWMonitor to watch the temps and speeds while the test is running. I simply chose to run the test under "Blend" as I am new to the hardware testing. However.... The clock speed of the CPU does not vary from 1996.4MHz at 100% load. I don't know if this is because of how Prime95 runs its test or if I have a faulty CPU. I intend to try some encoding to see if the clock speed increases under different circumstances.

Additionally, and perhaps relevant, I have a similar problem with the RAM. The clock speed of the RAM is rated and set to 2133MHz. Throughout the testing the clock speed of the RAM does not vary past 1064MHz.

Any Ideas? Is this something that I am just not understanding about Prime95?

EDIT: Okay so maybe I am an idiot but it wasn't till I looked at the Resource Monitor built into Windows that I saw the CPU is at 100% load but 48% Maximum Frequency. So I am a little less worried now, but still confused as to why Prime95 isn't pushing my machine to the limit.
 
It could be thermal throttling, what CPU cooler are you using? I know in my HTPC rig (A6-6400K) the stock cooler is basically crap, aluminium finned block with a fan on top! Tried with the cooler that came with my FX8350 and that wasn't much better! According to AMD the limit of your CPU is 71-72ºC, and i'm assuming it starts to throttle just shy of that temperature to try and not burn your chip up!
In relation to your RAM, if you are checking its speed through CPU-Z, the memory max bandwidth displayed is about half of what the RAM is actually running at (1064MHzx2=2128MHz)