ok.. are you sure the screen going black was not part of windows power saving feature? after 20 mins of not using it, maybe its just turned the screen off to save power?
i dont know what operating system ur using, mine is xp and i put it on a floppy disk, reboot my system and it loads automatically. think vista and win7 may be different, u will have to read and follow the instructions if thats the case.
unless ur just mistaking windows power saving for a black screen, in which case run occt again and leave it for an hour, come back and wiggle the mouse, see the results.