Hi, looking to upgrade my desktop and as I haven't been closely following new tech and hardware for a year or so I would really like some advice from the people in the know 
Currently running an Alienware Area 51
Intel Core 2 Duo E8400
Gefoce 9800 GX2
4gb DDR3 Ram ( but using less ******* 32bit OS grr)
NVIDIA nForce 790i Ultra SLI-based motherboard
Been starting to have a poke around to see what's been happening recently in the hardware world and really interested in the Radeon Eyefinity multi display tech. The card that has caught my eye pricewise has been the ATI HD 5870 series, would this be a good upgrade?
When I last knew a little bit about what I was doing the crossfire setup needed a crossfire specific mobo, but i have recently read something about it being compatible with normal SLI mobos these days, is that correct?
What would you guys recommend as a good upgrade to my current set up?
Would upgrading to windows 7 64 bit be worthwhile so i can sling another wad of ram in?
thanks for any help, it's much appreciated!!

Currently running an Alienware Area 51
Intel Core 2 Duo E8400
Gefoce 9800 GX2
4gb DDR3 Ram ( but using less ******* 32bit OS grr)
NVIDIA nForce 790i Ultra SLI-based motherboard
Been starting to have a poke around to see what's been happening recently in the hardware world and really interested in the Radeon Eyefinity multi display tech. The card that has caught my eye pricewise has been the ATI HD 5870 series, would this be a good upgrade?
When I last knew a little bit about what I was doing the crossfire setup needed a crossfire specific mobo, but i have recently read something about it being compatible with normal SLI mobos these days, is that correct?
What would you guys recommend as a good upgrade to my current set up?
Would upgrading to windows 7 64 bit be worthwhile so i can sling another wad of ram in?
thanks for any help, it's much appreciated!!