Help! i9 9900k Trying to Reach 5GHz 24/7 Stable

[xl3b4n0nx]

So I have 4 I9 systems that I need to get the best STABLE overclock out of. Here are the specs:

 

CPU: I9 9900k

Mobo: Asus Z390 Gaming-E

RAM: 64GB @ 3200MHz

Cooler: Corsair H100i Pro RGB 

Case: Rosewill RSV-L4000 (4U Rackmount)

 

Bios Settings are as follows: (Anything not listed is default) 

• XMP I profile enabled
• MCE: Auto
• SVID Behavior: Best Case Scenario
• CPU Core Ratio: Sync All Cores @ 50
• Digi + VRM -> Load Line Calibration: Level 6 (Might have the name wrong, writing this from home)
• Internal CPU Power Management -> IA AC Loadline & IA DC Loadline = 0.01
• CPU Core Voltage: Manual = 1.3V

 

The machines are in a 64 F server room so ambient temp is not an issue. They will be used in a compute cluster to run FPGA builds and simulations which can be AVX heavy workloads. They will be run 24/7 and potentially be running the overclock for years at a time so stability is key. My goal is to get all chips to 5GHz (AVX/non AVX). My problem is that I am running into temperature issues. I am seeing temps in the 90s and sometimes 100c on some cores. The weirdest thing to me is that there can be a temperature delta of 13c between cores on the CPU. I don't know if this is common to 9900K or just a bad cooler mount. When I run prime95 to stress test I either have an incorrect result/hardware failure or a thermal shutdown. We got these CPUs specifically for the lightly threaded performance and every MHz matters. So if anyone has any suggestions on better BIOS settings it would be really helpful.

 

I plan to check the mounts on the coolers. No additional thermal paste was added to 3 of them, so I have a feeling that may be part of it.

 

[Mister Woof]

If stability is key, I'd just leave it at stock imo

[WereCatf]

28 minutes ago, xl3b4n0nx said:

I am seeing temps in the 90s and sometimes 100c on some cores

5GHz AVX-workload with MCE enabled? Yeah, that sounds about right to me.

[WereCatf]

31 minutes ago, xl3b4n0nx said:

Cooler: Corsair H100i Pro RGB

Could always try swapping out for a 360mm AIO instead and possibly cranking pump-speed up as well.

[xl3b4n0nx]

23 hours ago, Plutosaurus said:

If stability is key, I'd just leave it at stock imo

We bought i series for the overclocking so leaving stock wouldn't make much sense. We already have 4 6700K and 7700K overclocked. Just doing the same with the newest platform.

[xg32]

the lowest voltage i've seen for 5.0 AVX is around 1.38v, even if it's 1.35v on a golden chip that's not something the h100i can handle.

[tincanalley]

Personally, I would turn off MCE.  Doing so allowed me to hit 5.1 and be stable.  So far I've been using the machine for video encoding, and other tasks and not one BSoD or other issue.   With MCE on, it crapped out doing simple benchmarks and other stress tests.  Not saying this will solve your issues, or get you higher speeds, but it isn't a helpful feature when manually OCing.