Can't reach 5Ghz, overly high 100C temp with AVX and Prime95

[MonarchX]

I am having issues with OC'ing 8700K my ASUS Hero X WiFi (latest 1503 BIOS). It hits 4.8Ghz stable at 1.328v on all cores with ASUS Enhancement disabled, C/P-States disabled, SpeedStep disabled, Load Line Calibration setting 5, VCore set to manual 1.360v. My Cryorig Universal R1 Dual Tower keeps CPU under 80C with AVX disabled (offset set to 0), but if AVX is enabled, then Prime95 (latest) small FTE (or FFE or whatever) makes my temps sky-rocket to 100C in no-time at all and I checked to make sure the cooler is properly installed. From what I understand, on non-delidded 8700K, heavy Prime95 AVX test can make 8700K reach 100C even on water.

The real issue is that i can't hit 5.0Ghz at all... Usually Windows 10 simply does not boot past 4.9Ghz, regardless of VCore... RAM is DDR4 Corsair Platinum Dominator 3200Mhz @ 3200Mhz 1T. Any ideas? Bad chip?

[NemesisChild]

What is your highest ambient temp and how is the airflow in your case?

What TIM are you using and how was it applied?

[MonarchX]

Arctic Silver 5 and pea'ish size on top/center.

[Zammin]

I was not able to hit 5Ghz on my 8700k without delidding and applying liquid metal, even on custom watercooling. Prior to delidding I ran 4.8Ghz @1.275V (in BIOS, 1.232V under stress test load) adaptive voltage mode and LLC4. I'm now at 5Ghz @ 1.350V (in BIOS, 1.31-1.33V under load) adaptive voltage mode and LLC5.

Your voltage seems very high for 4.8Ghz, have you tried following Raja's adaptive voltage overclocking tutorial here:http://edgeup.asus.com/2017/kaby-lake-overclocking-guide/3/?_ga=2.185832041.1973363672.1518950532-88...

You may also want to look at Der8auer's 8700k overclocking video on YouTube to see how to max all your power limits as well, otherwise you may see issues such as downclocking under load.

Following that guide I was able to get 4.8Ghz at a lower LLC setting and load voltage than my first attempt at manual mode where I used LLC6.

I think you will likely continue to have temperature problems when using voltages over 1.30V on the stock chip and air cooling.

[MonarchX]

Yeah, I was actually able to run 4.8Ghz @ LLC 5 @ 1.25v without issues after 1602 BIOS came out. The issue is that @ 5Ghz, CPU doesn't even have to get hot to fail to launch Chrome (which uses AVX), even @ 1.36v. That is why I don't think de-lid will help... Then again, I keep AVX Offset at 0 and maybe such expectations are overly high.

[Zammin]

MonarchX wrote:
Yeah, I was actually able to run 4.8Ghz @ LLC 5 @ 1.25v without issues after 1602 BIOS came out. The issue is that @ 5Ghz, CPU doesn't even have to get hot to fail to launch Chrome (which uses AVX), even @ 1.36v. That is why I don't think de-lid will help... Then again, I keep AVX Offset at 0 and maybe such expectations are overly high.

Yeah i understand. That's why i mentioned Der8auer's video guide as I suspect you may be hitting power draw limits or something. There's a few power limits that you normally need to max out when going for those higher clocks. Just an idea.

[xherics]

I was able do go for 5GHz on 8086K with water cooling, but temperatures were too high, between 85 and 97 C degrees under 100% load.

At 4,8Ghz it had between 78 and 86 C degrees, what is still too high. On stock it has 45-55 C degrees...

I think without delidding my piece will run just "on stock", I do not want to delid this one.

[xherics]

this post is a #mistake please delete it