It's been happening to all my Source engine based games lately. It's running fine, then it gets an uber choppy frame rate(i'm talking less than 1 FPS), and freezes. I can try to Alt+Tab out, but it doesn't actually tab out. I'm forced to reboot my comp to fix it. It happened after Valve released that news post about fragmented caches. At first only DoD:S would do that. Then CS:S would do it. Now Dystopia has done it. What should I do?