For the past few weeks, my computer has been freezing randomly - sometimes Windows dosen't even load and it freezes, other times it's either on the internet or playing a game. I got no clue what's going on, but in games I can see characters - and on the internet and other things with text I can see the letters outlined in purple/pink then it freezes. This has happened before, and last time it was something to do with my memory, I've changed out the chips twice now and it keeps on doing it. Any suggestions? Note: The system does not restart itself, the screen stays the same, but the mouse and the background all look right but it just freezes. I have not changed any type of files or installed anything to my knowledge that would cause such problems.