https://www.reddit.com/r/overclocking/comments/1rxghb1/2x8gb_ddr55600_cl46_overclocked_to_8400_cl36/
When I ran my 2x8GB DDR5 Hynix A-die kit above 1.4 VDD, it tended to crash around 30 minutes in Y-cruncher VT3 and AIDA, and no manner of adjustments to my VCCSA, VNNAON, and VDD2 seemed to fix it (my 2x16GB DDR5 kit can handle 1.65 VDD just fine). Because of this, I decided to settle on this 8200 CL40 1.4V profile. I found that 1.1 VNNAON is enough for 38x D2D, or maybe even 39x D2D, but I haven't stress tested that. 1.2 VCCSA is enough for 34x NGU.
————————————
DDR5 timings:
Frequency: 8200
CAS Latency (CL): 40
tRCDR: 48
tRCDW: 16
tRP: 46
tRAS: 80
Command Rate: 2T
Gear 2
tRRDL: 16
tRRDS: 8
tRFC: 496
tRFCSB: 384
tREFI: 262143
tWR: 48
tRTP: 24
tFAW: 32
tWTRL: 24
tWTRS: 6
tCWL: 38
————————————
Bios settings:
Power down mode disabled
Fast boot disabled (memory training takes like 30 seconds)
High d2d cold boot workaround enabled
Virtualization disabled
iGPU disabled
————————————
Ring/NGU/D2D:
42x ring, 34x NGU, 38x D2D
————————————
Voltages:
1.4 VDD
1.4 VDDQ
1.4 VDD2
1.2 VCCSA
1.1 VNNAON