Sell the 5850 and buy a 5770 instead, scaling of 5770 (~1.7x) is the best among AMD cards. 2x5770 overclocked = 5870 (Although some games do not support CF)
For PSU go for Corsair VX550W for 2x5770. And please throw that VIP PSU. You could also sell both the GPUs and buy a 5870 or GTX 580