Random graphical glitches in Windows 7

I was restarting my laptop because of some problems opening files and applications and it hung for about 10 minutes on the shutting down screen so I had no choice but to manually kill the power. When I tued it back on, I started noticing minor graphical glitches like:

The bench should not have that black graphical glitch.

I also noticed that the text in some applications is now much blockier (TeXstudio)

I also notice some more subtle jaggedness in icons and in general a washed out feel to the display.

I tried both rolling back and updating the graphics driver (Intel HD Graphics 5500, Lenovo T450 less than a year old), but no luck. I have also tried restarting, etc.

I am ruing Windows 7.

Any possible explanations for this? Would I be correct in saying it's a software problem? When I hover over the glitch above with the mouse pointer, for example, it still remains.