Not for hashing BTC..... Cancer Folding, and Editing porn......... or maybe I am shining some turd PCs for sale
How about all 3 at once?
Do they need 6 pin powers?
No 7750 will require a 6 pin PCIe power plug. The card only uses ~55W max. The 7770 uses ~80W, just a hair higher than what the PCIe spec can provide, so it needs one.