Garry's mod, half-life 2, and grand theft auto v constantly glitching!

I have a HP Pavilion TouchSmart 15 Sleekbook, with 4 GB Ram and plenty of disk space left. It has Windows 8.1 which isn't the best for gaming but does work! Most games work perfectly fine and look beautiful however many aren't right now and never did: namely Garry's Mod, Half-Life 2, and Grand Theft Auto V.

The audio breaks up, te textures sometimes get screwed up, etc! Grand Theft Auto IV is also acting up but I'm not sure if it's a "Source" engine related problem or not. Please help guys, I want to be able to enjoy my games! Cheers!
Asked Jun 30, 2014

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