Weak IMC or Bad RAM? (4000Mhz B-Die Kit on Coffee Lake)
I tried finding more info but was unable to, therefore I'm posting this. Little background, I'm familiar with overclocking and have been doing it last 15 years. I was able to reach Winbond BH-5 to 295Mhz 2-2-2-5 4.0V on a DFI NF4 back then.
HyperX Predator Black 16GB 4000MHz DDR4 CL19 DIMM (Kit of 2) XMP (HX440C19PB3K2/16) - I know they're not QVL.
I'm unable to POST on SPD1 (3600Mhz) or SPD2 unless setting relaxed timings/subtimings before hand, and then enabling SPD.
Even if booting, 3600 or 4000mhz is never stable with main timings as advertised.
Tried VCCSA 1~1.3v and VCCIO 1~1.3v and vRAM 1.35~1.45v
Tried Buildzoid's on memory OC on Z390 Aorus Master - Guide
Results so far:
While this kit is listed as 17-18-18 on 3600Mhz, I have ONLY been able to stabilize at 18-18-18-42 at 3600mhz (and with horrible tREF & tRFC...)
4000Mhz is not working even at 19-20-20.
Question: How can I identify if whether I have a weak IMC or if the RAM has to be RMA'd?
You may have a weak IMC but I would say your biggest problem is the Gigabyte MB and it's crap BIOS.
See if you can find someone who has posted a high frequency RAM OC on that MB and try copy there sub timings exactly.
To find out if the RAM is faulty test one stick at a time if one stick can hit it's rated speed and the other can not you know you have a dud.
what is wrong with the bios on the Master? I know they have come along way from how they used to be and are always looking for input to help them get better. At least the OP didn't get stuck with any of the Asus trash.
Haven't used gigabyte myself for some time so I could be wrong but more often that not when I see people having problems reaching high memory speeds it is with a Gigabyte\ASRock MB and the BIOS seems to be getting the training wrong for the RAM kit it is using.
While ASUS high end MB seem to be more likely to get it right and although ASUS VRM may not be as good provided they have some airflow they seem to do there job just fine even if they use a bit more power.