L4D2 and P2 crash when loading chapter/campain!

[RobZombitch]

Alright, I have had this problem for a while now and nothing seems to fix it. I have had so much trouble with source games that uses an updated version of the engine.



Problem:
Whenever starting either game, it starts as normal, nothing is going wrong at this time, I can access the menu and choose what gamemode I want to play in/what chapter I want to load. When I do click a campain(L4D2)/load a chapter or game(P2) it loads up normaly and then, boom. the sound starts looping and my screen looks like it keeps trying to adjust resolution or what not over and over again, until its finished and it plays this awful sound on a loop. After this I cant do anything, I cant interact with my PC, no Ctrl + Alt + Delete, I have to do a hard restart by holding down the button on my pc tower.


Notes: This did not always happen and its been happening recently, like for about a month now.
I AM ABLE to play very little of the games, like the very first campain in single player(L4D2) and 1 community map that I have (P2), I really want to find out what is going on.
I have tried verifying cache, nothing helps, I have tried reinstalling Portal 2, doesnt work, I have restarted steam/restarted computer/virus (full) scan. Nothing helps.
(Portal 2): Trying to create my own map in puzzle maker and playing it also does not work.
Other source games like L4D1, Garrys mod, Portal, Half life (1,2,2ep1,2ep2) Counter strike source, Day of Defeat, those all work. Its just the newer ones I am having trouble with.


Important!: I DID not play any steam games with the updated engine on my new computer that I got during the summer. After I got this new one its been FNAF, and minecraft all the time. I wouldnt be surprised if its my computer, that was I atleast know something hasnt gone completely wrong.
I started getting back into steam games right after the Christmas of 2k15.





If you guys can give me any advice/tips/info/answers that would make my year! Please respond as soon as possible!


PS: I heard Counter Strike: Global Offensive uses the same updated engine as these two games, I dont have it installed, but im sure it would do the same exact thing as L4D2 and P2.


Maybe some helpful advice: I am running on Windows 7