Short version of results:
S9 DC Draw at 12.1V == 1.89W/MHz + 57W
The 1.89W/MHz holds across at least 450 to 668.75 on this unit; the 57W is the controller and fans at 100%.
At 650 w/ 100% fan I see 106.67A @ 12.051V for 1285.5W.
50% fan reduces this to 1275W, hitting the S9 specification.
MHz | | DC W | | AC W | | PSU Eff. | | W @ Wall w/ Fan | | J/GH @ Wall |
450 | 855 | 968 | 88.3 | 1033 | 0.107 |
550 | 1040 | 1175 | 88.5 | 1240 | 0.105 |
600 | 1133 | 1281 | 88.4 | 1346 | 0.104 |
625 | 1179 | 1333 | 88.4 | 1398 | 0.104 |
650 | 1229 | 1391 | 88.4 | 1456 | 0.104 |
668.75 | 1265 | 1433 | 88.3 | 1498 | 0.104 |
PSU is a DPS-2000BB being fed 208V; voltage at PSU ranged from 206.8 to 208.7 during these tests.
All measurements taken simultaneously - Dedicated sampling for I & V on both AC & DC
+12V measured at the S9 board inputs ranged from 12.051 to 12.146, depending on load.
These DC Power draw measurements below _do not_ include loses in the 12V cables - these are dependent on your setup but may be around 10W; actual PSU efficiency is accordingly around 1% higher.