I just got a new pc. It has a r9 380 4 gb, i5 4460, and a 600 watt psu. When I tried a benchmark it was running at around 3-5 fps, and when I try to play tf2 it also got really bad frame rates. Sometimes they both run good but rarely. The guy at the store couldn't find anything wrong with it and said it ran well there. The integrated gpu is also disabled. There are other things plugged in in the same room including another computer does that have something to do with it?