my sleeper pc sorta

so the other day i took my moms old dell inspiron 660 and put a radeon r9 270 in it and put a solidgear 850w power supply in it then when i installed afterburner i overclocked it as much as possible. thats where it gets sketchy It has better temps now and runs the game almost as good as my 1060 oh and the r9 has the stock cooler on it
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oh and on the dirt3 benchmark it does better than my rig

 

Needs a new transmission

 

well my rig bottlenecks so bad thats probably the problem

 

i saw a sleeper pc on eBay, the outside had a windows 95 tower, with a GTX 1070 Inside, with a intel core i5. It was 250 bucks, i was going to get it, but then i realized i was poor