800 budget go for amd build. you can get phenom x2 and unlock the 2 cores and get a
6870 if you dont plan on crossfire in the future. if you want to crossfire get a 6850 good performance all around. samsung spinpoint or wd black hard drive and for memory get a ddr3 1600 or less. there are some nice mid atx case under 100.00 like cooler master haf or cm960 advanced. check out tiger direct or new egg depend which state you live they wont charge you with tax.