Hi, some reasons for
Blue Screens
New hardware - Software installed.
Device driver - Video driver - corrupted - faulty.
Faulty Ram - Overheating - Dying hard drive, etc.
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Is the same happening in Safe Mode?
Check Windows Advanced Boot Options
https://neosmart.net/wiki/advanced-boot-options-menu/
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Run a Mem Test.
http://www.memtest.org/
Scroll down to 'Download (Pre-built & ISOs)'
'Download - Pre-Compiled Bootable ISO (.zip)'
Download the ISO file then burn to a DVD.
You will have you use another pc to download the ISO file and burn to a DVD.
Start the Pc using the Cd and run the memory test overnight or for at least 8 passes.
It is best to run a full scan on individual Ram sticks if you can.
Or run the test but if any errors are shown - then remove all sticks of Ram - test each Ram stick one at a time and test them in different slots.
Guide to using Memtest86+
http://www.wikihow.com/Test-PC-Ram-with-MemTest86
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Run a hard drive test.
SeaTools for DOS tutorial - ISO to CD
http://knowledge.seagate.com/articles/en_US/FAQ/201271en?language=en_US
http://www.tacktech.com/display.cfm?ttid=287