Dismantlling a laptop in a well equipped workshop by an experienced technician is an easy job (but time consuming) however folks who are not either trained or experienced in delving into electronics and of course taking all ESD (anti static) precautions may want to consider carefully before taking this step. If you are experienced in these procedures and have a spare compatible component handy then go ahead and try a substitution…… However it might be wise to ascertain if it's a hardware issue or an operating system/software issue first.
If you disable the NVidia and just use the Windows graphics how does it perform?
You could also do a simple test by booting into a live distro of Linux (Puppy or Ubuntu are both good, with Puppy being a smaller download) Burn the .iso as an image and set your computer to boot from your optical drive with the Live Linux disc in the tray.
Give the machine a good work out using Puppy… if it works Ok then you have more or less eliminated hardware as a likely suspect (Don't install either Puppy or Ubuntu just run it live ( in Ram) as you don't want to write anything to your hard drive. When running the live disc in RAM when you shut down and reboot, then Windows will be back and Puppy will be gone!
If it's likely that it's software or operating system (as a result of the above test) then before doing anything too drastic like formatting and reinstalling, there are some basic checks and repairs you can perform that MAY fix the problem.
1 Run chkdsk with the r switch from a command promt with elevated privileges…. the command you need is:
chkdsk /r
accept the warning, type
Y
press Enter
type
exit
press Enter
Close down and then restart your computer (a full shutdown not a sleep/hibernate)
Don't interrupt chkdsk or allow power to be shut off, only run chkdsk when the PSU charger is connected, It may take several hours to complete and will make any repairs it can and then restart your computer.
2 From the same command prompt with elevated privileges run sfc
the command is
sfc /scannow.
Any repairs that sfc can perform will be done automatically.
3 Download Windows "all in One repair tool" from www. tweaking.com
read the instructions carefully and follow them all (note the need to power down and drain your machine in the correct way before restarting in safe mode with networking
4 Don't be tempted to skip the reg back up, system restore point. and back up everything that's important to you on your machine (anything you don't want to lose) and make sure you have at least one extra validated and tested copy, kept safe offsite on removable media.
5 You could try just the repair of Windows Update on its own, however in view of the problems you have been experiencing then it might be worthwhile you considering running all the repairs.
6 If you still have problems after all this then maybe its time to reimage your system. or perform a format and reinstall or upgrade to Win 10
Post back and let us know how you get on.
Regards
paws