I5 3750k gpu...

You could play almost any modern title with the HD4000 graphics, however, the question is, how smoothly will you be able to play those games. You'll most likely see very choppy FPS that are very inconsistent if you play on HD4000.

Anywhere from 5 to 50fps depending on game, resolution and details. You may end up having to use lowest resolution and detail to get playable framerates in the more graphics-heavy games.