I ended up returning the board and getting a different one from a different manufacturer. Worked first time.
ASUS support were great and immediately recommended RMAing the board via the vendor after I explained the issue and troubleshooting steps. I opted to purchase a different board as I didn't want to risk the same issue with a replacement given the number of people in this thread that share the same issue.
I'm hoping this info might help others:
I had the Z490-I , 2x32GB (3200mhz XMP, 16-20-20-39) (2400Mhz SDP, 17-17-17-39) RAM and an i7 10700KF.
Although some settings would increase stability, nothing completely fixed the issue and I would still get crashing every few hours under load.
I also had almost immediate crashing unless c-states were disabled. The testing below was performed with both c-states on and off. Nothing was ever stable with c-states on.
I tried:
- Updating BIOS to v707 - No change
- MCE off - No change
- Increasing the SA and VCCIO voltage - 1.1, 1.15, 1.2 - No change
- Increasing the DRAM voltage - 1.36, 1.4 - No change
- Relaxing the timings (17-20-20-42, 18-20-20-42, etc) - Increased stability
- Reducing the frequency (3000mhz XMP no change), (2400Mhz increased stability)
The only thing that removed the issue completely was populating only a single DIMM slot.
The most reliable way I found to reproduce the crash was prime95's benchmark function (not the stress test). Memtest86 always passed for me although I did limited runs as 64GB takes a long time to test!
