4790k Won't OC or even turbo.

[NiaNia]

Hello All!

I had originally gotten a 4790k because the ability to overclock was appealing. My intention was to eventually OC when my CPU started aging. The CPU is amazing and I haven't noticed any problems with it. However, when I was monitoring temps the other day I noticed something. My CPU only goes to 3499mhz, not even the 4ghz a 4790 goes to, and certainly not the 4.4ghz the K is supposed to turbo to.

I have reset BIOs, I have the latest bios version, and I know it's not throttling. When I look in CPU-Z it says my multipler ratio goes from 8-44, but the clock speed will never go above 3499mhz even under load. Any ideas?

4790k
z97x-sli
Be-Quiet! Dark Rock 3 (Non-Pro)
28gb ddr3

 

[iamacow]

Turbo isn't for all cores. I bet one or two cores is boosting to 4.4ghz. In some motherboard BIOS you can set turbo for all cores. You can thank Intel for that marketing scheme.

 

[luckymatt42]

Generally speaking, if you have left all of the Windows power options set to default, and your bios is more or less default (i.e. multiplier is not locked), it is normal for a cpu to "downclock" under heavy load with all cores.

See what happens when you run a single core benchmark/application. I'm pretty sure Cinebench has a "single processor" mode or benchmark. If your cooling is adequate, it should boost fairly close to it's maximum boost number while testing on a single core.

 

[NiaNia]

I snooped around in my BIOs and found my single core turbo. It was 44x, 44x, 43x, 42x on cores 1, 2, 3, and 4 respectively. I set these all to 44x. When I went to do cinebench my multi-core was 697cb and my single core was 143cb. When I looked in CPU-Z for my clock it was still showing only 3499mhz on both tests. Are these numbers consistent?

 

[luckymatt42]

First, probably dumb question, but you are checking the speed WHILE the benchmark is running?

Otherwise, double check your Windows Power Plan, try setting to the Ultra/High Performance option and see what that does.

 

[NiaNia]

Yes, that was while I was monitoring. I averaged around 800-1600mhz at idle and 3499mhz at load. Following what you said, I have set my settings to "Performance." Now my idle is at 4400mhz. CineBench Scores have improved dramatically, especially single core. During multi-core load my CPU sit's at 4ghz, and during single core 4.4ghz.

I may have to go into BIOS and reset my multipliers to fix the idle at 44ghz, but either way I am satisfied for now. (I may be back when I start OCing, we'll see how that goes.)