https://www.cnet.com/products/alienware-x51-r2-dt-core-i7-4770-3-4-ghz-8-gb-1-tb-ax51r29300bk/specs/ Those are my specs, it is indeed a prebuilt. Had this for 2 years, but when i'm playing a game like League of Legends, my fps is capped at 120 and i always get 119, legit 1 less than my capped for some reason, and sometimes randomly this will happen. I put it on very low graphics which is horrid looking and it still happens. Background programs are not the problem cuz i looked at task manager usage, have not monitored temps or anything, just wanna know where to start, cuz i'm always at 120 fps, and this happens randomly and it screws my experience. Also, I don't know if this could be a problem, but sometimes my headphones get tangled so when i turned around, my computer fell, this has happened up to 4 times and the 2nd time or so, when i started it up, it had to repair hardware. Tell me where to start to fix this. EDIT: By the way, a few days ago, figured out my ethernet cable was not plugged in but doesn't seem like this fixed it.