The closest you will get in dropdown is 268.75 which is 1085GH/s ...bitmain really needs to update the firmware for these but they do a great job for heating with minimal noise
Ambient room temp is 72F
Depending on which batch of C1 you have, there are different fans on the rads...it will either be 3 fans plugged into 2 headers which are the more powerful fans, or 1 fan into each of 3 headers which I believe are the first fans that were used....the lower powered fans use .1A less than the stronger ones not sure of exact numbers but there is a difference
When Im done testing the Avalon for efficiency I will plug the C1 in to my APC and see how much power it draws at different frequencies...give me a day or 2 time permitting
I was looking for underclock not overclock..
Also my firmware allows me to do 275 freq, Maybe u need to update ur miner