Right now I'm just going to transfer my existing GeForce 8800 GTS 320MB card for video so I can compare speeds with my existing build (see my profile for system specs) before upgrading to a CrossFire or SLI build. The new GTX 275 catches my fancy but basically my question is:
Assuming I get two top-end video cards in SLI or Crossfire for this new build, what size power supply do I need?
I'm thinking the 850 Watt range using a good quality brand, but I've been out of the "Power Supply" loop for a while and I'm just not sure what the great brands are. I like Antec, but I'd also like to know what other brands are good. Remember I want something that will last me a while, but not something that is overkill for what I'm getting. To clarify, I will likely never have more than five SATA drives (including optical) at a time, and will never use more than two video cards for SLI/Crossfire.
You're correct, a quality 850W PSU will safely power a system like yours with up to SLI GTX 285's. The Corsair 850TX is a very high quality PSU. Other quality PSU manufacturers are PC Power & Cooling and Seasonic. Pretty much any PSU from those 3 manufacturers are a sure bet. Antec makes good PSU's, but they also make some cheap PSU's. OCZ, Zalman, BFG, and a few others fall into the same category IMO.