I was also looking into Costco's desktop which is currently offering the ZT Affinity 7337Xa Desktop
Phenom II X4 945 3.0GHz
Microsoft® Windows 7 Home Premium
19-in-1 Media Card Reader
Gigabit Ethernet LAN
Integrated ATI Radeon™ HD 3100 graphics with DVI
Does anyone know about ZT or the ATI Radeon HD 3100 graphics which is also an integrated graphics card?
Not really sure why you're sticking with integrated graphics. At any rate, they have motherboards with built-in Geforce 9300 graphics chip for around $100.
I think you might be setting yourself up if you go with Intel GMA 4500 or ATI HD 3100.