Dell M6500 freezing (Win10 64-bit, AMD Radeon 5800, 20 GB RAM)

I have an older model Dell M6500 that ~ expect for this annoying issue ~ is just brilliant ~ it breezes through both Illustrator and Photoshop ~ and even Vinyl Master Pro (a resource hog if there ever was one).

But it freezes and no amount of mouse movement or key-inputting will unfreeze it. I've done tons of research and the main culprit seems to be a buggered NVIDIA graphics card. Finally, it seems that either the solution was to either replace the faulty card with an ATI model or to tweak the settings in the NVIDIA's driver utility. 

But my card is an AMD Radeon 5800. 

The freezing is happening more and more often now. At first, it was once every three or four weeks, if left unattended for a while. Then, it became once every other week. Now it's nearly every 24 hours. It's even frozen whilst I was actively using it.

And there seems to be no real common denominators (at least none that I can easily see). One moment it freezes, I have Illy, Photoshop, Mail, Chrome, and Vinyl Master open. The next, I literally have NOTHING open. The next, maybe Mail and Chrome. There really is no pattern that I can see ~ except for it being powered on, of course.

I've updated my drivers, tidied up my registry, and cleared as much unnecessary files off as possible. I really don't know what else to do.

I would absolutely love any and all suggestions, please and thank you in advance. Xxx