GRUxTSAR :
Good PC for what? For gaming that's overpriced for what you're getting. Get 8gb RAM, 4690k, switch 970 for R9 390x, throw in a SSD and upgrade that PSU to something more-suited for the build
He DID list 8GB RAM, and the 390x isn't going to help if he's playing at 1080p. Plus it costs $100 more than a 970. The ironic thing is the 600w PSU is actually more appropriate for the more power hungry 390x you suggested.
I also find it odd you're making it sound like your suggestions will help him afford an SSD, because the less expensive CPU and more expensive GPU are a wash, and you assumed he was needing more RAM. Even if you hadn't misread the RAM, a 100w less PSU is not enough to afford an SSD, and in fact 600w as I said is the rec amount for the GPU you suggested.
A lot of oversights for a so called "gaming expert", but hey, this IS Tom's, where awards are handed out like candy.
http://www.techpowerup.com/reviews/MSI/R9_390X_Gaming/30.html