I have to say that, looking at the manual I found this particularly unhelpful - no reference to BIOS, sleep mode, etc. but there you go. You should be able to switch this off in the BIOS setup, if you can work out how to enter the BIOD setup - it should tell you when you first switch on. If this does not work, I can only suggest that you deliberately switch the laptop to hibernate or sleep (see P2-11 of your manual) and it should then come back to like quite quickly by switching it on normally.
Incidentally, if you don't have the manual, click here.