I wanted to add some DPS-2000BB efficiency numbers to this thread, as I've recently been measuring DC and AC draw on my S9 at various clock speeds.
Counting 12V cable losses, I'm seeing 88.3 to 88.7% efficiency everywhere from 800W up to 1400W DC. Ignoring cable losses the efficiency is 89.7 to 90%.
This is all at a 208V input voltage... efficiency should be higher with higher input voltage but I haven't been able to test that yet.
so far I am getting good numbers with his board on the dps-1600 psu.
I am waiting for the second board and the dps-2500 psu
The goal will be to run them on my pdu that has an amp meter.
right now I am running his one board with the dps-1600 psu and running an evga 1600 p2 the two are driving a pair of s-9's batch 2 set to freq 600
the pdu reads 10 amps and bounces to 11 amps rarely which would mean 2400 to 2640 watts for about 25.0-26.0th
so far so good.