for some unfathomable reason, it looks like MoBo makers did not get the memo about the improved memory controller on 14nm+(+) Coffee Lake so they keep shoving the same voltages as Skylake. From my own testing and lurking BIOS forums, seems that most MoBos default to 1.30VccIO and 1.35VccSA for 3600Mhz and up. Some of them apply 1.25VccIO and 1.30VccSA for 3600Mhz but anything above gets the bump to 1.30VccIO and 1.35VccSA. Some of them (ASRock) even raise VccST from 1.000V to 1.200V which is absolutely not needed at all unless you're overclocking with LN2.
for
4000Mhz (no matter what CAS), the voltages should look like:
· 1.200VccSA ± 0.025
· 1.150VccIO ± 0.025
· 1.000VccST (fix it to 1.0 and never care again, this voltage is NOT related to memory OC although some MoBos raise it when enabling XMP)
· VDimm depends on your particular setup and silicon quality, but this setting is written on the SPD of the DDR4 stick so if you're not tweaking latencies just use the Auto XMP value.
so I'd guess that for your
3600Mhz XMP @ChrispyjBMW the BIOS settings should be close to:
· 1.150VccSA ± 0.025
· 1.100VccIO ± 0.025
· the usual fixed 1.000VccST in case your board mess it up like mine does when enabling XMP
· Auto VDIMM (1.35V)
Alternatively, you can try the same voltages I used for 4000Mhz but don't overshoot because it won't help stability, it will in fact make the memory spit out errors more frequently. Your Vcore seems enough and the WHEA_UNCORRECTABLE is usually related to memory so give it a shot.