If he's not into gaming, photoshop or anything else demanding, I'd get him a 2-3GHZ dual-core or maybe a decent Pentium 4 with 2GB of RAM. Also consider him just using the on-board video card if he's not too much into graphics. One of the computers I use is a Intel Pentium 4 3GHZ with 1GB of RAM and on-board video... It runs Windows 7 very well indeed even though I prefer better since I do some gaming too.