Sounds like insufficient voltage issue, specifically the System Agent voltage (VCCSA).
After applying XMP, try increasing it a bit like 1.25-1.35v (depending on strength of your CPU's integrated memory controller AKA IMC).
Weak IMC means you will need to pump more VCCSA.

I use Hyper Pi 32m or Memtest-HCI: http://hcidesign.com/memtest/

For Hyper Pi, pretty much straightforward. Just run the 32m test with full core/thread

For Memtest, use one instance for each CPU thread.
At least 500% no error

delidding service
If you have the courage to do it by yourself, can consider buying this Delid kit

Good luck!

Wow didn't know that you have a delid tool bro!
Actually I also have one Rockit as well, haven't used it yet.
I think I will not delid my 7700K, resell and buy 8700K instead bwahhaha

To be able to see your CPU operating at the desired frequency (4.5GHz in your case), change your power plan to "High Performance":


Use CPU-Z to to check your CPU frequency.
Use Core Temp to monitor your CPU core temperatures.
Alternatively, HWInfo64 can be used to monitor both CPU speed and temperatures etc.
Download links available in the top post of this thread.

System crashing has many possibilities, check the BSOD message.
It could be due to overheat, wrong BIOS settings or insufficient voltages (vCore, vDIMM, VCCIO, VCCSA etc).
Most probably is insufficient vCore that feeds voltage to the CPU.
I saw your're using Load-line Calibration (LLC) level 4, which could cause too much vDroop (load vCore is too low). Perhaps you should try the lower level to reduce vDroop, best would be level 1 (minimum vDroop).
If LLC level 1 still crashing, then you should increase your vCore, notch by notch until your system is fully stable.

This post has been edited by owikh84: Sep 13 2017, 10:33 PM

Easy right? Haha you're welcome bro
Btw, CPU-Z is not a CPU stressing tool, not even a good software for benchmark.
Run Prime95, LinX, OCCT (these 3 very stressful and too hot), AIDA64 Stability Test (less stressful), XTU, Realbench, etc.

Unfortunately I have have any good temperature data to compare with yours, but my last 6700K at stock clock (4.2GHz) registered around 55-65C at full load in AIDA64 under a custom loop powered by a pair of 360mm radiators. It's hard to tell unless we have identical systems to compare with each other.

Recent gen Intel CPUs, including the 6700K have thermal issue due the ineffective Intel thermal paste used and excessive gap between inside the chip, which cause inefficient thermal dissipation between the chip die and the integrated heatspreader (IHS).

Anyway Prime95 is an unrealistic punishment of a CPU, generating a lot of heat compared to daily usage. So it's quite normal to see insane temperature during the stress test. Perhaps you should try reducing the vCore to shave off few degrees?

Yes it's worth. 7700k is a hot chip right out of the box, due to the poor TIM and excessive gap between the IHS and chip's die.
At a mild OC like 4.6GHz you won't see much of the heat output, but when you go higher then only you will notice the hotness reaching 100C.
Delidding will give significant lower temperatures by around 20C off, which is a huge figure.

My chip runs at 5.0GHz @ 1.275v and the temp during gaming is 80C while stress testing can reach as high as 90C.
Hotter temp means my cooling fans will spin faster, resulting in the increase of noise level.
By delidding my CPU, my chip should be able to run at ~70C with a lower fan speed and much quieter.

Why OC till 5.0GHz? Because you can get extra performance and remove possibility of any CPU bottleneck.

Yes, that's the only disadvantage of CPU delid

I own a lot of chips, so far zero RMA case

Congrats on your purchase, welcome to Coffee Lake club.

Is that your best vCore or can it go lower?
Did you notice any vdroop (load voltage drops too much from BIOS set)?
What's your vCore set in the UEFI BIOS, CPU-Z idle and load?

P/S: I'm also waiting for my 8700K from Active Lancing

What Prime95 version are you using?

v26.6 and below have no AVX/FMA3 instruction
v27.9 has less stressful AVX, no FMA3
v28.5 and newer has stressful AVX+FMA3

Edit: I can see FMA3 in your SS so should be one of the latest versions.
Your CPU core temps look great.

This post has been edited by owikh84: Oct 18 2017, 11:09 AM

OC Guide for GIGABYTE Z370 board, top post updated.

[JOOMAG] GIGABYTE Z370 OC Guide



This post has been edited by owikh84: Oct 18 2017, 11:57 AM

Officially jump on the bandwagon...

ROG Maximus X Apex and TUF Z370-Pro Gaming are here.


Let's start with the Apex


First thing to do is of course to overclock the i5-8600K CPU to 5.0GHz (BIOS set 1.425v, LLC5) and run Cinebench R15:

CPU score: 1221 cb (7700K @ 5.0GHz: 1087 cb)

Currently, I am also testing the LLC in Realbench 2.44 (AVX) to see the vdroop/vdrop. This is just part of the results:

LLC works fine for me, vdroop = -0.016v, despite ROG Strix Z370-F users are complaining about 0.08-0.09v vdroop.


Also note the core temps, idle @ 57.3C, load @ 85.3C, which are in my opinion a bit on the high side.
Cooling is custom loop lowered by a pair of 360mm radiators in push-pull fan configuration.

Still under 100C , not bad for a 8C/16T CPU actually.
Reducing the uncore/cache speed could shave the temps off a bit if you're not planing to delid the chip.

Extracted from KBL OC guide but should also apply to CFL as well.

https://edgeup.asus.com/2017/kaby-lake-overclocking-guide/5/

This post has been edited by owikh84: Oct 20 2017, 08:54 PM

No idea as I have not tested the TUF board yet.
All of the ROG Strix models except for Strix-H have recently received a BIOS update to fix the LLC issue.
Seems like LLC issue on the TUF series and Strix-H will not be fixed by ASUS.

https://rog.asus.com/forum/showthread.php?9...-UEFI-0419-0426

Did I just hit the silicon lottery for my retail 8700K?
Batch L729B568 with VID 1.088v.
5.0GHz primed stable for 3 hours @ 1.280v at full load (BIOS set 1.30V, LLC5).
core temp 79C max (76.5C average, ambient @ 30C non-AC room).



CPU: Intel Core i7-8700K (8C/16T) (no delid)
Mobo: ROG Maximus X Apex (BIOS 0601)
RAM: G.Skill TridentZ RGB DDR4-3200 C16 2X8GB
GC: ROG Strix GTX 1080 Ti OC SLI
SSD: Samsung 960 EVO 500GB
PSU: Corsair AX1200i
Cooling: Custom WC



Should I delid the chip?

Extreme4 (RM 800) has better VRM quality than the TUF-Pro/Plus, for smoother power delivery to the CPU.
Extreme4 does not have LLC issue with the latest BIOS update while there's no solution for the TUF.
However, both don't have debug LED for error troubleshooting.

If you have more budget, can consider the Fatal1ty Gaming K6 (RM900+) with a debug LED, onboard power/reset buttons, dual Intel LAN ports with teaming support.
Add RM 100 you can get the Taichi (RM 1000+) with dual Intel LAN + Wi-Fi, 3x M.2 slots.

Some Cinebench R15 benchmarks with my undelidded 8700K...

5.0GHz @ 1.216v
5.1GHz @ 1.264v
5.2GHz @ 1.344v



Of course, Prime95 29.3 would demand higher voltage hence hotter.