Power consumption numbers:
1200Mhz - 120-130gh - ~115-120w on my killawatt
1100Mhz - 112 - 118GH - ~107W
1000Mhz - 98 - 109GH - 98W
Have not tested 800 yet.
These results are the same as I am seeing.
I seem to gets lots more HW errors at 1000 MHz compared to 1200 mhz.