Hi Brendy!
Lucky you, that's a kickass computer imo! XD
Hum.. for the CPU, just be aware, the best deal you can get right now would be Phenom II X6, Its currently at 179$ on Newegg, so it would unfortunately bust your budget a little.
The AMD Phenom II X6 1055T is getting 28.78 passmark points [(CPU Mark / $Price )] for 179$
The Phenom II X4 955 would be a little below 4,267 passmark points for $144.99 (maybe more since its black edition??)
http://www.cpubenchmark.net/cpu.php?cpu=AMD+Phenom+II+X6+1055TAlso I have read on an overclocking forum that you cannot change the CPU/NB Voltage on your Mobo , so that could be an issue, but since you are cooling with 2 stock casing fans, and that you did not purchase an after-market cpu heatsink, I assume you wont overclock.
Cool setup!