4770K OC

[tongey54]

@Fiery

 

Hi,

 

I have a 4770K overclocked to 4.7GHz @ 1.225V with memory at 2666MHz. When all tests are selected in the Stability Tests, it passes for 24 hours @ 85C. If I select the FPU test only, the CPU almost instantly throttles. I know this is considered 'unstable' but what are the chances of any other normal use application getting my CPU to these temperatures? I hear the FPU test uses AVX instructions which are quite rare in real world apps. 

 

The system seems perfectly stable in games and hits around 80C after a few hours (mainly due to the GPU heating the case up).

 

I've tried getting a stable OC where the FPU only test stays below 80C but I'm almost back to stock volts/frequency to achieve this. I have a Corsair H60 whcih has cooled a 2500K and 4670K before it with no issues at all.

 

Your thoughts please?

 

Thanks,

[Fiery]

The FPU subtest of AIDA64 System Stability Test is designed to drive processors to their absolute limits.  That's why it uses state-of-the-art techniques like AVX and FMA instructions.  Before Haswell hit the market, we considered throttling processors (while running the Stability Test) unstable.  However, with Haswell we all simply have to get used to the fact that due to the FIVR (integrated VRM) the CPU can indeed throttle under heavy load, and still work stable.  So if you're okay with those high temperatures, or you believe the FPU subtest of the Stability Test is too extreme and wouldn't align with your normal, everyday usage scenario, then just ignore the throttling and use your CPU at 4.7 GHz.  However, in case your system turns off due to the high temperature while e.g. running a 3D game, then you should consider improving your system cooling

 

Regards,

Fiery