I'm currently running a single 5770 on my p5q deluxe (1 PCI-E @x16 or 2PCI-E @x8), and I'm considering purchasing a second card for xfire because I'm impulsive and bad with money (get paid that xmas bonus soon
). Do I
a) get another 5770 because they scale well and will be more than enough for a good year or more's gaming
b) save up and get a 5870, selling the original 5770 (while they still go for near £110) to make room for a 2nd 5870 further down the line when I feel the need.
???????????????
A) gets me great performance now at an affordable cost, but doesn't set me up for longevity
B) is expensive as hell, but hopefully by the time I can afford another one I'll have a board that's not limited to x8 in xfire and I'll be able to play current DX11 titles for a good while.
What do you guys think?

a) get another 5770 because they scale well and will be more than enough for a good year or more's gaming
b) save up and get a 5870, selling the original 5770 (while they still go for near £110) to make room for a 2nd 5870 further down the line when I feel the need.
???????????????
A) gets me great performance now at an affordable cost, but doesn't set me up for longevity
B) is expensive as hell, but hopefully by the time I can afford another one I'll have a board that's not limited to x8 in xfire and I'll be able to play current DX11 titles for a good while.
What do you guys think?