When screen is locked, the champions when moving, and blurry. Not when unlocked.

Title explains it. When i have locked screen (y) the champs look blurry when pathing. Ive tested on 2 accounts, and set both graphics to default. My computer is not very bad, although i have half of my hard drive disabled. But that has not been a problem before its been that way for a few years. It might be client side, or a bug idk. I have not reinstalled or uninstalled because it doesnt bother me that much, and i can play unlocked screen. Just kind of annoying. Thanks