Poor OC results - Z370 Taichi + 8600K

RPGWiZaRD wrote: Setup: 2x i5-8600K .... (not delidded)

Edited by Dmytro_o_o - 03 Aug 2018 at 3:56am

Old post I know (I'm bored while my coffee is being made), but the i5 8600k is generally known as one of the best kept secrets for gaming, many overclocking to 5.1Ghz with ease (Delidded helps a lot).

A delidded 8700K should hit 5Ghz all cores, even if you have a mediocre sample.

Quick BIOS settings:
The older BIOS versions seem to be better, but the Microcode to protect from security flaws is important to me, so I stick with v3.10 - no need for going higher as they are really for 9700/9900 series CPU's.

Fixed Voltage (this board lacks adaptive voltage, and the offset implementation is not the best.
Fixed voltages are perfectly safe if not stupid:
Start at 1.36V and you can safely go up to 1.41v for daily use, assuming you don't plan on keeping this CPU for more than 10 years. :)
LLC Level 1 is just the best option on these Z370 AsRock boards.
Turn of Multi-Core Enhancement
All Core Overclock
Multiplier x50
Cache x45
Min x44
VCCIO @ 1.05v
VCCSA @ 1.08v
BCLK Spread Spectrum - Disabled
AVX Offset - Auto (same as 0 - thanks AsRock, lol)
BCLK Aware Adaptive Voltage - Disabled
Intel Speedstep - Disabled
Intel Turbo Boost - Enabled (you can't overclock without this enabled)
Intel Speedshift - Disabled
Long Duration Power limit - 4095
Short Duration Power Limit - 4095
CPU Core Current Limit - 255.00 (you can type 300 and it will default to max)

DRAM should be XMP 2.0
DRAM Frequency - choose your RAM's XMP speed instead of leaving as 'Auto'
Primary Timings - type in the actual timings instead of Auto and just type the number '2' in place of Auto for 'Command Rate'
You don't need to touch anything else in DRAM.

Run 'Realbench' 30 minute stress test to ensure stability.
If BSOD then only adjust Fixed vCore until you are stable
Use HWInfo64 (sensors) to keep an eye on vcore/temps etc when you are stress testing.
vCore should remain pretty stable with only small vDroop under load - that's why LLC is really the best option for higher end OC's on this board.

I'm running delidded 8086k @ 5.3Ghz all cores - 1.39v (Got lucky with this chip).
Idle temps are 28-29C in room with Ambient of 72F (22.2C)
Under full load in Realbench, average temps are 67-69C with occasional spikes to 72-74C which are well within specs.

I gave up on trying to use the Offset voltage method as it's just not good - why they didn't implement proper 'Adaptive' voltage is beyond me.
Higher voltages at idle (within reason) won't harm a CPU.
What kills CPU are High Current AND High Power usage

I'll probably ditch this board and pickup an Asus Hero z370 board as I'm pretty sure my CPU will do 5.4Ghz, but this board is too 'loose' anything over 5.3Ghz.

Hope this helps.
Good luck