Question I7 8700K CPU Downclocking while gaming

Erik91

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Dec 29, 2014
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Hey guys

Lately I've been noticing that my CPU downclocks at random times while gaming, causing FPS drops and stuttering.

It runs at 4295 MHz most of the time, but sometimes it downclocks to 800~1100 MHz and other random clocks which causes stuttering.

The only thing that stopped that was to change the CPU minimum power to 100% on power plan settings.

But I don't think that is the ideal solution since it keeps the CPU running warm all the time.

My CPU is not overclocked. It's running at 1.250v.

And another odd thing is that I tried to run some tests on prime95 (Small FFTs), it ramps up the clocks to the max value 4300~MHz at 80c for a few seconds, then my CPU just downclocks to 3600MHz at 65c and stay there.
Is that normal for a torture test?

Is my CPU or Power Supply dying?

I have C-State on Auto.

Thanks in advance.
 
Running max turbo for 30-60 seconds (4300 MHz is the normal all-core turbo of an 8700K), then adopting a lower than max but normally above minimum 'base clock' is normal behavior....

Dropping down to as low as 800-1100 MHz while still under an intensive load (gaming is intensive, just not 'Cinebench'-level intensive) however is NOT normal....

I'd install Intel's XTU, and remove power and boost duration limits, but, stay at "Balanced' model in WIndows power plans...(this will allow maintaining peak turbo boost under load indefinitely, barring overheating, yet, still allow downclocking to 800-1100 MHz when simply loafing at the desktop)
 
just try loading optimized defaults and see if it continues to cause issues in-game.

you should also have an OSD showing system temperatures while any game is running so you can see if temps may be corresponding to the lower clock speeds.

if it is just cycling through lower c-states when heavy processing is going on;
it would definitely mean some error either in the BIOS settings, Windows, the motherboard, or the CPU.
 

Erik91

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Dec 29, 2014
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Running max turbo for 30-60 seconds (4300 MHz is the normal all-core turbo of an 8700K), then adopting a lower than max but normally above minimum 'base clock' is normal behavior....

Dropping down to as low as 800-1100 MHz while still under an intensive load (gaming is intensive, just not 'Cinebench'-level intensive) however is NOT normal....

I'd install Intel's XTU, and remove power and boost duration limits, but, stay at "Balanced' model in WIndows power plans...(this will allow maintaining peak turbo boost under load indefinitely, barring overheating, yet, still allow downclocking to 800-1100 MHz when simply loafing at the desktop)

Thanks for the reply!!

I actually tried to put the Motherboard on Performance mode, and it worked, no more core dips while gaming.

For my surprise even with the Intel Speed Step and C-State disable my CPU would downclock on low usage.

Maybe something is bugged?

Power plan still on balanced