SSDs use virtually no power. Another card, on the other hand, would definitely need a more powerful PSU.
I didn't realize you weren't in this for gaming. In that case, the CPU/GPU sounds good. Now you need a better mobo. A P67 board will let you overclock the 2500K, which is a VERY good idea. You don't have to crazy with it to get a lot of free performance.http://www.newegg.com/Product/Product.aspx?Item=N82E16813128487
It's got all the basic goodies (USB 3, Sata III), but it won't handle SLI/Xfire, PSU or no PSU, so think about whether that's in your future.