Hey guys I need help cleaning out files of this laptop I just got. It has a 150GB hdd but 120GB are being used... I can find some files but theres around 100GB that are being used.

I would normally just install a fresh windows but the problem with this laptop is that it overheats if the processors aren't in power save mode (Shuts off in 20 or so minutes if its not in powersaving) any suggestions?