The R7 200 series card varies widely. I just moved away from that R9 380 about a year ago, and the R7 265 appears to compare. The 240 and 250 aren't as great.

That said, this build can probably do games in low and sometimes mid graphics. I have seen lower spec machines than this play newer games, but graphics takes a hit. You would probably get much better performance out of running Linux on the machine. Mine struggled in Windows, but Linux was just fine because of newer drivers.