I'd make an addition, but it seems you're evading the issue so its more for anyone else planning on upgrading. PSU's can be tricky; some less reputable manufacturers claim "1000W" and the like, completely ignoring the amp requirement (the larger the number of amps it can handle, the more stuff you can plug in, in lay mens terms), splitting things up to a ridiculous number of rails (say its rated at 20A over two rails. That's 10A per rail. If one rail has too much on it, say goodbye to the PSU and possibly anything on that rail).
For anyone else thinking of doing something with their PSU, don't fuck around with unknown brands, fork out for a reliable one; they don't give you more connectors than you can use without blowing something. £20 for a better PSU is far cheaper than replacing your mobo/graphics card when the cheap one overloads and fries everything. Corsair are good, but look to see what you need; I know the 650W has something along the lines of 10 Molex connectors (plugs into fans), 8 SATA (plugs in HDDs/CD/DVD-RW) and 2 PCI-e. Unless you're running a beast or simply want to make sure you have room to add stuff later, it might be overkill. Then again, they'll last longer than any other component in your PC. *shrugs*