Windows 10: PC crashing 20 minutes after I turn it on

This has been happening for a while now but has gotten worse recently.After I turn on my PC it takes about 20 minutes before both my monitors freeze, the audio continues for about 10 seconds then stops. Sometimes I get a constant buzzing sound through my headphones too. I can't cntrl-alt-del, I can't do anything apart from restarting my PC with the restart button or just powering off. If I just leave it, it restarts on its own after about 3 minutes.After I restart I won't likely get this problem until the next day when I turn it on after it's been shut down.It's more likely to happen if I open

:)

 

Suddenly, BSOD every 15-20 minutes


As the title suggests, my PC has been running fine, up until last night, playing Fallout 4, suddenly BSOD. Today, I turn it back on, and it crashes booting, then crashes over and over every 15-20 minutes, giving me many different types of errors, including page file, security, etc. The crashes don't seem to be related to anything I'm doing, just random.

Log file attached as per instructions. If any additional details are needed, please let me know.

Thanks in advance for any help, this is maddening.

 

all games crash!

I suggest you run rthdribl > http://www.daionet.gr.jp/~masa/archives/rthdribl_1_2.zip
Increase the window size step by step and watch your vga temps permanently.
What happens?
If it crashes, run at stock speeds as suggested before and retry.

P.S.: When your system locks, does the display signal turn off after a time?
Stuttering sound or no sound at all when freezing?
What X1800XT model do you own exactly?

 

Wifi connection cutting off every 20 minutes

My internet is turning itself off about every 20 minutes, and I have to go to the network and sharing center and run troubleshoot wifi connection 3 a several times before it goes back to normal.

What I've checked:

• The internet works without fail on my phone. The problem is surely on this device.
  
• The wifi connection 3 thing on network and sharing center is the thing that always goes offline (has a red cross next to it)
  
• My intelligence... I'm pretty bad at computing so please explain this in steps.
  

I'd really appreciate it if someone could tell me how to stop this inconvenience from occurring every 10-20 minutes, its really frustrating. I need to answer questions and get more reputation on writers SE .

Thanks. By the way, I ran a scan. Its not a virus or malware, whatever else it could be.