cgminer: WU vs Hashrate on SHA-256. What are your results?

[Bagpipe]

I stumbled upon a weird occurence. My HD7950 is clocking some 630MHash/second, but in the stats of the pool it reports more than 710MHa/s on AVERAGE. I believe this is due to the WU being >9.5 compared to 8.8 before the cooling mod.

What is your WU (work utility) and MHa/s on SHA-256? (Bitcoin and such)


I have currently:
HD7950, 630MHa/s avg. (long term), WU=9.5 (long term avg.)


What did I do that it is so efficient?

[Bagpipe]

Something more: when the card is cold, the submitted WU rate can be as high as 20/minute, it is sending work out like crazy. It is not directly related to the temperature on the GPU chip, but maybe to temperature of some other components.

At 52°C on the Tahiti Pro2, the whole card takes 180W from 230V net. As the temperature rises to 62-63°C, the power input too, to 191-192W.

I noticed this as I was modifying the cooling, that something else is changing the rate of work utility per MHash rate other than just the clock.

The most stable results are 1.380 to 1.500 WU per 100MHash/s. Just a coincidence of numbers?