More than enough. This isn't one of those [insert crappy maker ie: Deer] 300w units masquerading as a 450w'er.
[edit] BTW, in case you don't know, they have a *5* year warranty - same as the more expensive HX line. There's not really anyone else in the industry that matches that (most 2 maybe 3 TOPS). Ultra is a bit of an odd duck w/ their Lifetime coverage. Must do within 30 days, online, or it's only 1 year...And good luck getting prompt service - but from Corsair, it's not going to be an issue.