3 year old PC, is this PSU enough?

mike789

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Jan 19, 2012
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HI.
I have used a couple of wattage calculators but the results are quite marginal so I'd appreciate any input.
The system is about 3 years old and has a couple of power hungry components as opposed to newer generation hardware. Specs:
asus p7p55d-e evo
intel i5 750 @3.8ghz (stock 2.66)
powercolor radeon 5850 @900,1200 (stock 725,1000)
2x4gb corsair vengeance ddr3 ram @1600
2x500gb HDD 7200rpm
dvd-rw
4 case fans
1 extrenal hdd, 1 printer, webcam, mouse, keyboard
The psu is a corsair HX750, and the question is because I ll be putting a second 5850 in crossfire (I found one identical a friend has no use for) and plan to have them OC'ed at least @850,1150.
Thanks!