As my motherboard has 3 PCIE16 slots, I'd ideally like to add another card (probably a Sapphire 5850 Extreme). My question is, can my power supply handle it?
Just wondering if anyone has tried anything similar on a 750W PSU? I have the advantage of having a good, efficient PSU, but still I'm not sure if it'll handle it.
The Corsair should be able to handle another 5850, especially if you don't clock the hell out of it.
I was drawing about 275VA on a 5870 924/308 stock voltage with a standard 80+. So actual draw is about 220W. Adding a Sapphire 5850 Xtreme and swapping to 750W 80+ Silver PSU took me to 470VA with the 5870 at 930/310, 5850 at 924/308, actual draw about 438W or 218W for the additional card and CPU 1/3 load due to updating to the bugged Catalyst 11.6B, so that makes the 5850 about 200W overclocked or 160W at 725/300.
So estimating from that (since running only one of my 5870 or 5850 at those clocks reaches the same 303~305W at the wall), I'd say a stock clocked 5850 would bring your system total to roughly 600~650W. Even if all of that was +12V, it's 87% of the AX750's +12V capacity. Pushing it but still within safe limits I would say.