Need advice on overclocking an i5 8600k processor.
Need advice on overclocking an i5 8600k processor.
Hey there!
I purchased my first K processor, which is an 8600k. I decided to slightly increase its speed within safe limits because the turbo was reaching 4.2, aiming for around 4.5 ghz.
I have an MSI Z370 A Pro mobile motherboard. So far, I’ve looked through several guides on the basics and adjusted the multiplier ratio to 45. I changed the voltage from auto to first 1.176, then 1.185, and finally 1.2.
I ran Prime95 on the "small ffts" test, which I think is a stress test for the CPU. Initially, at 1.176, all 6 workers stopped immediately. At 1.185 it didn’t stop, but it behaved similarly to 1.2—running for about 15 seconds before dropping back to 4.5ghz while the cores were still active.
Here are some videos for those who are experts; I’m sure they can provide more details.
Without stress test at 1.2:
With stress test at 1.2:
I might also miss any motherboard options since I just changed the two settings I mentioned earlier.
The available settings are:
Also, without any changes, the basic settings kept a temperature around 35°C, and during the same stress test it reached 68-70°C.
Any assistance would be greatly appreciated.
Prime95 relies on AVX instructions which can cause extra heat generation since most users won't actually use them in real-world scenarios. Most BIOS systems have a setting such as "CPU Ratio offset when running AVX" that is typically set to -9, 900MHz or 20%, effectively reducing clock speeds during AVX operations. You might turn this off (or set it to 0 if you can't disable it), use Prime95 version 26.6 which avoids AVX stress, or try a different stress test like OCCT. http://www.ocbase.com/
Barty1884 discusses how Prime95 uses AVX instructions which can cause excessive heat generation since most users won't actually use that feature in real-world scenarios. Most BIOS systems include a setting such as "CPU Ratio offset when running AVX" which is typically set to -9, 900MHz or 20%, effectively reducing clock speeds during AVX operations. One option is to turn it off or set it to 0 if possible. Another approach is to run Prime95 version 26.6 instead, which avoids stressing AVX. Alternatively, consider using a different stress test like OCCT. It might be worth checking the BIOS options for power-saving settings that could help manage the temperature. If you're interested, I can share pictures if you have time.
Cstates are present yet they shouldn't affect anything during high load.
Are there any options to turn on "high performance" in the Windows Power Plan settings?
Barty1884:
Cstates are present but shouldn't affect anything under load.
Is "high performance" active in the Windows Power Plan settings?
I've adjusted it to high performance. It seems unchanged; I discovered a BIOS option to list more settings, which adds more questions.
I reset the "cpu core voltage" back to auto, yet it displays the old value of 1.2.
Should I adjust something in Ratio mode, ring ratio, enhanced turbo, or another setting related to llc?
Additional question: Should I disable AVX only for prime95 since it never gets activated during games?