Why wont my laptop Start up?

If it won't boot past the bios screen (And you did not spill no coffee on it, or accidetaly mistook it for a soccer ball, or anything else that could be considered as our own fault), then you need to try to reset bios... if you can get inside the notebook enclosure without killing the warranty, unscrew the back cover, find the bios switch/jumper on motherboard and toggle it to "reset cmos' for a good 5 minutes, then look what happens. If you can't get inside it without ruining warranty, then put on your sports shoes, quickly run to the retailer and ask for warranty service. If it is a motherboard thing, your data on hard disk drive should not be corrupted and i guess that if you ask them kindly to either drop the data to a other mean of data carrier, they will be able to do it (or transfer the same hard disk in-to your new machine, in case it needs to be replaced)... and always remember to backup your data regularly in order to avoid such worries in the future.... EDIT: Try detaching all mechanical devices from the MB... hard drive(s), DVD-Rom... see if it's still "clunking" and try to detect the source of that sound. PS Are you sure you did not drop it or anything?

Take the computer to a computer store and see if they can retrieve your files from it