Computer Keeps Crashing And Requiring A Restart

Intel i7- 4770
16GB of ram
64bit windows 7
GTX 780

A few days ago I was playing overwatch with some friends. My computer can run most games fine and I usually run Overwatch on the highest settings perfectly. But that day after playing for some time my computer randomly froze, I couldn't move the mouse anymore or use the keyboard and there was no sound anymore. I could still see the game on the screen but there were some small artifacts on the screen like small purplish and pinkish shapes.

I had to restart the computer to be able to use it again, but ever since that crash happened my computer has not been right...

Now my computer crashes every time I open a game. Sometimes if I restart the computer I get a blue screen on startup but sometimes it loads fine. Sometimes just opening a text editor is enough to cause the computer to freeze again, some application seems to freeze my computer while others don't. Luckily for some reason, the internet browser does not cause the computer to crash. Some applications like Skype seem to just cause the computer to slow down a lot but not crash it. When I open the task manager I noticed that sometimes the CPU usage is erratic. Like it will be 0 one second and then 100 the next and then drop back to a normal level so that made me suspect it could be a CPU issue, but the artifacts on the screen that I get when my computer freezes after opening a game make me suspect it could be the graphics card.

The computer seems to run fine in safe mode.

Not sure what's going on but would appreciate any help.

 

I would check the temps with Speccy download here Speccy 1.32.740

I would all so do a Air dust to your desktop.

All so give use a picture when using Who crashed.

Download Who crashed here WhoCrashed Free Home Edition 6.01

Give us a Crash report.

 

Check to see if you have any minidump files as follows and I will analyze for you.

Minidump files:
Click on Start menu
Type in command to start searching
Right click on Command Prompt in list and select Run as Administrator
Copy and Paste the following command into the command console
This will create a new Minidumps folder on your Desktop and copy any of your minidump files into it.
Compress the Minidump folder to .zip file and upload to your reply

MD "%userprofile%\desktop\Minidumps"&
If Exist "%SystemRoot%\minidump\*.dmp" copy %SystemRoot%\minidump\*.dmp "%USERPROFILE%\Desktop\Minidumps"

 

It could be software, or hardware. How long have you been running this card? How old is your power supply? Is the machine properly surge protected? Has there been any storm/lightning related activity recently?