Question 9700k Overclocking Issues

soratoyuki

Reputable
Dec 18, 2016
18
0
4,510
Hey guys. Total OC newb, unfortunately. Either I've lost the silicone lottery bad, or I'm doing something really stupid.

9700k paired with an Aorus Pro Wifi board.
Mugen 5 rev B air cooler
EVGA 2070 and 16gb G.SKILL TridentZ.

On stock, my idle temps are low 30s and run Prime95 in the upper 50s.

I've finally tried to overclock, and everything makes Prime95 freeze my computer almost instantly. I've tried (with AMP on, enhanced multi-core performance off, and uncore at 4.7g. I haven't messed with LLC because every guide I've seen refers to numbers but Aorus uses Auto/Turbo/Extreme?):

5.0g, 1.32v
5.0g, 1.30v
4.8g, 1.30v
4.6g, 1.32v

Then I went back and tried, just for good measure

5.0g, 1.35v, -2 AVX offset

All of them had the exact same conclusion. I boot up HWiNFO64, Speccy, and Prime95. Run it. Temps go up to the upper 50s. I get excited. And then my computer goes totally unresponsive. I wait with bated breath, give up, and restart my PC.

Please tell me I'm doing something monumentally obvious and dumb and I just need to flip a no to a yes or something.
 

soratoyuki

Reputable
Dec 18, 2016
18
0
4,510
I haven't. To be totally honest I didn't fully understand what uncore did, just that the Gigabyte overclock guide said to start at 4.7. Do you have any idea where I should set it?
 

soratoyuki

Reputable
Dec 18, 2016
18
0
4,510
I updated the BIOS just in case, and went ahead and dropped uncore to 43. It idled around 40c (a bit higher than I'd like tbh), and ran Prime 95 for 15 minutes before temps startred creep into the 80cs and I shut it off. Still, a pretty big improvement since nothing else went 5 minutes without freezing.

Where should I go next? Should I run Prime95 longer despite the temps? Should I start raising the uncore again or start with dropping the voltage?
 

zx128k

Reputable
You need to dial in the vcore voltage and overclock frequency for the cores. Aida64 would be a good stability test for this and can be found here Aida64 download link. Run this program for a few hours just to make sure your cores are stable. Then dial in uncore. I would keep vcore under 1.35 volts, as that's what many videos recommend for air cooling. The lower you can get vcore the better temps will be.

For example in some video's the uncore is set to 45 (cache min/max) and the core frequency to 5GHz. Then they run stability tests. Usually aida64 for 8 hours or so.

Coffee Lake RefreshSSE FrequencyAVX2 FrequencyVcore% Capable
9700K4.90GHz4.70GHz1.337V100%
9700K5.00GHz4.80GHz1.350VTop 90%
9700K5.10GHz4.90GHz1.362VTop 38%
9700K5.20GHz5.00GHz1.375VTop 9%
9700K5.30GHz5.10GHz1.387VTop 1%

The top two would be what I would aim for on air.

Remember you are on decent air cooling [1], so expect temps to be high. 80c is not bad. ~90-95c limit, >95c worry. Remember with air cooling, ambient temperature will affect maximum temps as it varies and also case temps/air flow. You want to leave some gap between the overclock maximum temps and the 100c thermal throttle limit.

Also if you can, watch the vrm temps to make sure your vrm's are not overheating and make sure there is good air flow over them. Your air cooler should take care of this. There are programs like CPUID HWMonitor etc that can help you monitor temperatures.

[1] Cooler performance https://images.tweaktown.com/content/8/3/8320_31_scythe-mugen-5-rev-cpu-cooler-review.png

Notes:
"Uncore" is a term used by Intel to describe the functions of a microprocessor that are not in the core, but which must be closely connected to the core to achieve high performance.

Uncore wiki link