Asrock z390 Taichi+DDR4-4000: Metro Exodus as system RAM tester

[80251]

I've been fighting to get my G.skill Ripjaws V F4-4266C17D-32GVKB to DDR4-4000 on my Asrock z390 Taichi (an infamously bad motherboard for memory overclocking) and managed to get it to 4006Mhz @ 1.45V V-DIMM. I then tried tightening the secondary/tertiary timings down and ran memtest86 for 12.5 hrs. (6 runs), then an orthos 6 core test with maxed dataset size for 4 hrs., prime95 with large FFT's for 2 hrs. and then the built-in windows 10 memory test and all tests passed then Metro: Exodus began crashing every time (and corrupting the auto-saves). After increasing the V-DIMM to 1.65V the crashes completely stopped. It's bizarre to me that a game would be more sensitive to unstable memory than all the memory and CPU test programs I used.

 

[Dr. Dro]

Running very heavy workloads for stress testing only tend to mask stability problems in lighter or bursty workloads where the voltage transients tend to overshoot or overdrop

That's why I insist on running Prime95 in blend mode instead of just large FFT, and keep ASUS's RealBench around (basically a script that loops lots of relatively heavy production programs)