Seemingly Random BSOD - Slowness After Most Recent?

I just built this computer around the 1st of August this year. It's my second self-built PC and came together without issue. However, I started having blue screens about once a week since maybe the 2nd day after I first ran it. Every single blue screen seems to be linked to the video card drivers crashing. Usually the drivers will crash and successfully recover as stated by the helpful little message at the bottom right.When the display drivers crash, I'm usually in a game of TF2, League of Legends, or even in Mozilla Firefox. The screen will freeze, sound will continue, and after 15 seconds or so go black for 2-3 seconds then go back to normal. The display driver crashing has happened TOO MANY TIMES TO COUNT and seems almost entirely random. Sometimes it will crash 3-4 times in the span of a half hour in League of Legends and sometimes it can go several days with no crash and the same amount of activity on the computer.

I've tried everything I could possibly find on the internet and from friends in terms of troubleshooting the display drivers crashing. I've diagnosed my memory, updated drivers, tried older driver versions, updated everything Windows has recommended, checked temperatures constantly... I'm starting to wonder if all of these issues could possibly be linked to insufficient dedicated memory on the video card? It says 1 GB on the box but when I check in system information it says around 750 MB... which sounds dangerously low to me.One more thing... the blue screens have happened 4 times so far, the last happened about an hour ago and the computer has been sluggish since, I can't even use Firefox due to how painfully slow it works now.