my brothers computer has a problem when he tries to turn his computer on it goes onto the loading screen for a long time and sometimes just turns off and sometimes it finnaly loades and goes into diskcheck so i let it go because sometimes there are problems at it stops of 42% and doesn't move even if i wait 4 hours which i did so i powerd it off and another time i skipped the disk check and it turned on but went really slow and then powered off. so basicly i can't turn his computer on. any help anyone? and sometimes the power button doesn't work i have to unplug his power cord plug it back in then wait a few seconds then turn it on but it still slows down