would this make a decent gaming pc if i threw in a decent PSU an GPU just looking for advise on this pc thanks https://www.ebay.com/itm/Dell-Optiplex-790-990-Tower-250GB-Win-7-Intel-I7-Quad-Core-up-to-3-8GHz-8GB-WiFi/232361199065?_trkparms=aid%3D111001%26algo%3DREC.SEED%26ao%3D1%26asc%3D20160908105057%26meid%3D1b640674a1354f61b716fe562af4e516%26pid%3D100675%26rk%3D3%26rkt%3D15%26mehot%3Dpp%26sd%3D183354464969%26itm%3D232361199065&_trksid=p2481888.c100675.m4236&_trkparms=pageci%3Aec9644f7-1bf1-11e9-85e6-74dbd1804a34%7Cparentrq%3A6665670a1680ac88dad45fbcfffe156d%7Ciid%3A1