So I would go with the FX470 given its generally faster speeds except for my concerns about overheating and power capacity (I have a 700W OCZ slipstream). With the case I just bought (http://www.newegg.com/Product/Product.aspx?Item=N82E168...) would having two FX470's cause significant heating issues? And would I have to get a more powerful PSU to handle two of them, along with the i5/p55 chipset? I also want to keep things as simple as possible and I have not done a dual GPU setup before, so is either one known to be easier to set up in Crossfire/SLI?
Well, in 2 years there will probably be cards twice as fast for the same price. It all depends on your resolution... lower resolution i would recommend the 5700 series cards, for medium resolution the 5800 series cards / gtx 470, and the max resolutions the 5970 and the gtx 480. Hope this helps!
Thanks for the comments - my monitor will be a 23" running at 1920 x 1080. In maybe two years the price for either of the cards should be around $100-$150, and I figure I will get another one so that my dual-GPU setup can still match the better single GPU cards available by then. So I definitely want to make sure I make the right choice with the first card (and will be of course using it to play new games until then).
I figure that the ATI 5850 should be able to Crossfire with even standard coolers, and work fine on a 700 W PSU w/ an efficient i5, as its voltage and heat seem to be quite low from the reviews here. I'm guessing, though, that SLI'ed dual FX470's will require more than a 700W PSU and probably a very good air cooled case or liquid cooling to run safely. If anyone here has a FX470, I would definitely like to know your experiences with its cooling and power requirements, mainly so I can rule it out
Indeed, if you are planning a dual card setup in the future then the HD5850 is a much better choice. SLI GTX 470s are going to need some serious case air flow and a ton of power. In fact a single GTX 470 uses about as much power as 2 HD5850s