BSOD playing any game, BCC 0x0000003b

I've recently been getting multiple BSODs a day and most of them I've managed to fix, but this one(0x3b) I can't seem to stop.
It pops up whenever I run a video game(Tera and Aion), doesn't matter if I'm running around loading maps or just staying in the same spot. It hasn't happened when not running a game though, if I'm remembering correctly.
Dumps from SF Diag tool attached.

I've tried

• chkdsk -r, no errors
• updated any drivers that were listed in past BSODs
• repaired both games
• uninstalled Avast antivirus prior to the two minidumps attached and installed AVG.
• uninstalled and removed all amd graphics driver files with driversweeper then re-installed latest driver(same one I BSOD with though...)
• reformatted and reinstalled windows, though I used a system image to restore to from when I wasn't BSODing 24/7 dated 8/4/2013
• tried swapping out RAM sticks

Unfortunately, you have a counterfeit installation, you appear to have a OEM_SLP key on a retail motherboard, please format and install with a genuine key.

I bought the computer from someone who was reselling it. If its counterfeit then I guess I was lied to. I'm not exactly rolling in cash to purchase a new windows, I'm just looking for some help with these blue screens.
I don't believe it's the cause of my blue screen either, if you could please help with that I would really appreciate it. Fix one bsod and a new one just pops up, pulling my hair out over here

Also just got another bsod 0x3b listing dxgmms1.sys in the error while running a game. I can post the minidump if anyone is willing to help.

https://www.sevenforums.com/general-d...ease-read.html

Great. Thanks for nothing.