i run 3 cards on a 750w psu ( 700-725w at the wall )
That's easy...some cards only pull 15watts!
The poster I was referring to was running 3 7950s (underclocked).
If he was running these under load (scrypt mining/over clocked) he would not be able to run them with a 850psu. Additionally he would be burning a lot of wasted power because of the efficiency drop.
sorry i ment to say i have 3 7950s runing at 630kh each
edit 1050 core 1250 ram 1.050v core 55% fan
Oh, ok. That's quite good.
But you still would be at (or near %) capacity of psu which kills your power efficiency. You must also be running other low draw hardware (like ssd/lower mem/ semperon/Ect). Like I said it depends on a ton of factors. And every online calculator I have seen would recommend a larger psu for those 3 cards.
Edit...re-read your post...you are at about 97% of capacity.
that rig is a 1090t cpu 256gb ssd cpu watercooling ( 25w waterpump ) 6 120mm fans 8gb ddr3 1600and a led monator lol have a look at it its my card testing rig / gaming rig lol
edit its a hx750 psu so max it can pull from the wall 850w ( at 90% efficiency )