Upgrading Pavillion 6600 with gpu and psu

Hello Tom's Hardware forum!

Recently I bought a Pavillion 6633w-b. The specs are:

amd athlon ii 255 3.1 ghz

5gb ddr3

640gb hd

23 inch monitor



I couldn't find info on the box about the power supply (bought it at wal-mart, not on display) so when I got home I looked it up and found out it has a 250 watt power supply . I want to play Starcraft 2, Civ 5, and maybe WoW on the pc (which I don't think are too demanding), so I went out and bought a gt430 because it only required a 300 watt power supply. Well when I woke up today I had a change of heart and took the gt430 back. I picked up a 600w gs600 corsair and a radeon hd 5750.



So now my question to the forum is will these new additions fit into the pavillion 6633w-b? (I haven't opened anything yet, I figured I would ask first, but I'm dying to play with the new toy!) The dimensions on the psu are 150mm x 86mm x 160mm. I think I read that any ATX will fit but I'm just making sure. I don't know the dimensions on the 5750.



Also when I started out my intentions were not too add the power supply and the better video card, but now that I have, should I just start over with a different cpu or is the amd athlon ok for this machine? I got a deal on the computer, but I don't want to suffer performance because of the cpu and will switch it out if necessary.



Thanks in advance!

As long as the PSU is not some strange proprietary size for your hopefully normal 'midtower' case, you should be ok....