One day, when I woke up and turned my computer on, it suddenly just became so slow, when I move the mouse it hangs then moves, hangs then moves, i turned off my pc and touch the insides of my cpu and realized it was overheating. This never happened to me before, all the fans are working fine, and I did nothing to my computer for this to happen. I tried reformatting my PC and it worked fine. But when I plug my usb dongle, it suddenly goes slow again and it overheats again. But my keyboard and mouse which are connected via USB doesn't have this problem. It also suddenly says that the usb port is 1.0 (for some ports) even if they're all 2.0 (Only when I plug my usb dongle). How should I troubleshoot/fix this? I currently have this large fan facing my CPU right now which is aweful.
I don't think this is overheating problem.. Still, confirm it using Speedfan(CPU temperatures below 60 deg Celsius are okay).
As far as USB ports are concerned, don't use a dongle for USB. Especially for devices like pen drives and hard drives.
To me, dongle seems to be the culprit.
Hav you tried operating the keyboard? I mean, is it just the mouse that lags of it is entire PC?