Basically my PC has been crashing when I play games on and off for about 2 years now. I noticed that these crashes only occur when I play games that are graphically demanding. I tried to get help at various points over the 2 years and tried various solutions such as cleaning the dust out of the inside of my PC and inside my PSU, replaced (upgraded) my RAM as I saw some people say this may be the cause and changed settings in Nvidia Control Panel. Each time I thought I fixed the problem, except when I replaced the RAM, as the freezing and crashing would stop, however the problem has come up again and now I really do not know what the issue is.

The latest fix I tried was to change the setting in the Nvidia control panel for Power management mode to 'Prefer Maximum Performance' which fixed all my freezing and crashing problems, however I've been playing Fallout 4 recently and in the last couple of days I've started getting these CTDs and freezes again. I should point out I have not touched the inside of my computer for months (apart from dust cleaning a month ago) and I have not made any changes to anything really in the last couple of days that I believe would cause this.

When I look online it doesn't really seem like anyone actually knows how to fix this, I've tried reinstalling windows and reinstalling my drivers from scratch so many times, neither of which ever worked. I'm starting to think that the problem has surely got to be the GPU or PSU but I really have no clue at this point. I have all the latest drivers and I have cleaned my PC with CCleaner but my PC still CTDs when play Fallout 4. I should also point out that I've been playing Fallout for about 5 days with no issues at all. When I do get a crash, the game will freeze and a buzzing noise comes from the speakers. Sometimes the game will close and it will say the Nvidia driver stopped working or that windows blocked the use of the drivers and other times the game will just freeze and I have to hold down the power button on my PC to shutdown.

I will include a DxDiag report with this as well as the Log file from GPU-Z which I ran during one of the crashes. Any help is appreciated I just really don't know what the problem is at this point. Thanks

http://imgur.com/8zeqjDc <---- Pic of GPU-Z sensor page during Crash

http://www.fast-files.com/getfile.aspx?file=116325 <----- DxDiag report

http://www.fast-files.com/getfile.aspx?file=116327 <----- GPU-Z Sensor Log during Crash