Unstable OC i7 6700k - suggestions?
Hi, returning to overclocking after a while - my last posts here were for an old 2500k (first build) and I found people here very helpful so thought I'd ask again.
Current System Basics:
CPU: i7 6700k
Heatsink: Be Quiet! Dark Rock Pro 4
Mobo: Asus z 170 Pro
Power: EVGA 850w
GPU: GTX 1080
RAM: 16gb Trident Z 3600mhz (but running at standard)
Phanteks Evolv X, with 2 Noctua fans/1 original phanteks in the front for better cooling.
So, for the first year or so was running at a decent 4.5ghz OC, good enough for most games. Recently I've found increasing the overclock can result an a decent FPS bump in some games (GRW and Dishonored 2) especially
at 1440p/4k. So was quite easily able to raise it to 4.6ghz, running at about 1.28 vcore under load. I'm using adaptive voltage as my mobo doesn't seem to allow me to set a manual voltage (something about enabling a jumper
for overvoltage- I assume that's a hardwired thing on the mobo that you have to change to get manual voltage control).
Recently bought a new cooler (Be Quiet! Dark Rock Pro 4) so decided to push the OC further. I can just about get to 4.7ghz but only by increasing effective vcore to 1.35 (Adaptive with no offset) and LLC 6, resulting in a vcore of between 1.344-1.376 under load, measured with HWmonitor.
AI overclock Tuner = Manual
BLCK = 100
Asus multicore enhancement: Disabled ( I read this wasn't worth the extra heat/power - doesn't seem to help FPS)
Multi = 47
CPU Svid = Auto (I found disabling this prevents boot)
LLC = 6
CPU Core Cache - 255.50 (Min and Max = Auto)
System Agent = 1.1 (found this helps slightly with stabilizing)
Speed States = On (switching them off doesn't seem to help the stability)
EIST = erm...can't find this in BIOS
XMP off (enabling seems to induce crashes, and also adds 5 degrees to the max temp).
Everything else on Auto
This will pass IBT standard with temps topping out around 90, and probably prime 95 but I don't like leaving it burning for ages as it sometimes nudges over 90 (version 26.6). Also doesn't crash in games, seems stable with temps maxing in the 70s. However it crashes in Cinebench almost immediately, and Realbench as soon as it starts the h.264 compression.
Is there anything else I can try to stabilize this, or even push the overclock up further (probably not I realise!). It just seems like a big vcore increase needed to go from 4.6 to 4.7, and won't go any further without running hotter than I would like. Also seems quite hot considering the size of this cooler. I've re-seated the cooler, both times using thermal grizzly kryonaut.
I've updated BIOS and chipset drivers, also GPU drivers - didn't really help.
I realise all chips are different, and I've probably hit the wall with this one, but just seeing if anyone has any suggestions really...or should I delid....
Any advice appreciated! Thanks.