I bought an emachines that had a PCI-E slot and i've turned it into the computer in my sig. I have had no problems with it and it comes with very little preloaded crap that most other companies have, i.e. HP, Compaq, Dell. So emachines gets a thumbs up from me. BTW, i got one with the ATI Xpress 200.
AMD 64 3200+ Newcastle@ 2.2Ghz
1GB (1x1GB) OCZ Performance Series
ATI X700 Pro 256MB OC\'d 475/525
OCZ Modstream 520W
Samsung 914v 19\" 12ms LCD
SB X-Fi w/ Logitech Z 5300e