I want to say I was at 1.7 but IIRC the asus overvolts vdimm by about .04 to .06
I should warn you that was ghetto cardboard box around ram with DI.
Can't explain it but when pushing hard AMD platform really cranks the heat up on the dimms even at low voltage, adding voltage seems to tick the ram off more.
The UD5P will pull 940 6-7-6 at 1.7v on c3 with ease, no need for DI, it's not to fond of pulling in TRCD to 6 though for max clocks.
Testing showed 1808 6-6-6 was faster.
Maxxing out these sticks is tricky on AMD, pen and a pad and full manual tuning while cold is a must at least for 32m type stability.

