Hi Kendo. I'm Greg, 10 times awarded MVP, here to help you.
There is a known issue with working fixes for random restarts, but since you've already identified the cause as your GPU, first let's do everything possible to fix it:
1) The Display driver is so important here that merely updating it is sometimes not enough. So let's try everything possible to get it working correctly:
First make sure you have updated the Display driver from the PC or Display adapter maker's Support Downloads web page for your exact model number, HP Serial Number or Dell Service Tag - from the sticker on the PC.
While there check also for newer chipset, BIOS/UEFI firmware (very important), network, sound, USB3 and other drivers, comparing to the ones presently installed in Device Manager reached by right clicking the Start Menu.
While there check also for newer chipset, BIOS/UEFI firmware (very important), network, sound, USB3 and other drivers, comparing to the ones presently installed in Device Manager reached by right clicking the Start Menu.
If necessary first remove the old driver using DDU
https://www.wagnardsoft.com/content/ddu-guide-t... (not necessary with Microsoft Basic driver which is a placeholder if nothing else is available) and/or installing in Safe Mode with Networking (so you have internet), or Safe Mode, accessed by one of these methods:
https://translate.google.com/translate?sl=auto&...
If new driver still won't install DDU see Lightning Leon's Answer here:
https://translate.google.com/translate?sl=auto&...
If this doesn't give you the latest or ideal driver for what you need, compare it to the driver offered by the Intel driver update Utility here:
https://translate.google.com/translate?sl=auto&...
or the Nvidia GeForce scanner here:
https://www.nvidia.com/tr-tr/geforce/geforce-ex...
or the AMD autodect utility here:
https://translate.google.com/translate?sl=auto&...
For Display issues one fix that is working is to Roll back or Uninstall the Driver on the Display Device > Driver tab, restart PC to reinstall driver.
You can also try older drivers in Device Manager > Display device > Driver tab > Update Driver > Browse > Let Me Pick.
Then you will know you've tried everything in addition to Windows Update drivers.
Adjust the screen resolution until it fits and looks best at Settings > System > Display.
Expedite Windows Updates to see if a new monitor driver is delivered.
2) If none of those fix it then try reseating your video card, remove and examine under bright light, blow out any debris with canned air, reseat firmly.
3) If that doesn't help then try another video card that's most recommended for your mobo and CPU. If it doesn't help you can return it.
4) Try the fixes which work most for random restarts:
https://windows101tricks.com/windows-10-freezes...
https://techcult.com/fix-computer-restarts-rand...
https://www.thewindowsclub.com/windows-computer... (Avoid ad links which intrude into editorial copy, especially avoid Restoro and Reimage ads)
https://troubleshooter.xyz/wiki/fix-computer-re...
https://windowsreport.com/random-restart-window... (Avoid ad links which intrude into editorial copy, especially avoid Restoro and Reimage ads)
https://www.reddit.com/r/buildapc/comments/8zd1...
https://support.hp.com/us-en/document/c03413399
https://howtofixwindows.com/windows-10-computer...
5) If none of those help then Go over this checklist to make sure the install is set up correctly, optimized for best performance, and any needed repairs get done:
http://answers.microsoft.com/en-us/windows/wiki...
Start with Step 4 to turn off Startup freeloaders which can conflict and cause issues, then Step 7 to check for infection the most thorough way, then step 10 to check for damaged System Files, and also Step 17 to test a new Local Admin account. Then if necessary continue with the other steps to go over your install most thoroughly.
6) If nothing else works then do a Repair Install, by installing Media Creation Tool, open tool and choose to Upgrade Now. This reinstalls Windows while keeping files, programs and most settings in place, is the most stable method to advance to the latest version, and solves most problems.
http://windows.microsoft.com/en-us/windows-10/m...
7) Test the RAM overnight to stress it with the best bootable test memtest86, following this guide to test both sticks and slots:
https://forums.tomshardware.com/faq/how-to-test...
Run Crucial System Scanner to check the RAM is precisely spec'd and configured, what upgrade options exist for first quality RAM:
https://www.crucial.com/usa/en/systemscanner?cm...
8) Test the hard drive or SSD with diagnostics:
https://www.lifewire.com/free-hard-drive-testin...
https://mashtips.com/ssd-health-test-and-perfor...
Best is to use the HDD/SSD manufacturer's own if there is one, otherwise use Seatools bootable long test:
http://blog.nowherelan.com/2013/04/04/boot-seat...
Follow this up with a full Disk Check from the Command Prompt in Repair Mode or from bootable media:
https://www.groovypost.com/howto/check-hard-dri... if necessary from the Command Prompt at boot:
https://www.tenforums.com/tutorials/2294-advanc...
9) Stress test the rest of your hardware:
https://techguided.com/best-tools-to-stress-tes...
I hope it helps. Based on the results you post back I may have other suggestions if necessary.
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