With some configuration work I have my Sapphire 280X Dual-X running at about 730kh/s so everything is pretty decent for mining. With my electric costs currently being around 0.12$/kwh though, I definitely need to look at dropping some of the watt usage.
The Voltage seems to be locked on this card at 1.225. I was able to use Sapphire Trixx to change the value to 1.125 (any lower than that and it made the driver crash). I noticed that when it is changed here though, it doesn't reflect in CGMiner. Does changing it in TRIXX actually reduce the voltage? Is there any applications that will actually show the watt usage? Would flashing the BIOS help at all?
*Edit*
I just noticed that GPU-Z shows the VDDC Power now which is apparently the Watt usage of the card. Is this pretty accurate or is there anything else that needs to be factored in? It is fluctuating between 80-107W right now which seems quite low for a 280X.