Keyboard not lit up and screen blank but on. Running hard

I would get another hard disk, replace the old one with it, and plug your old hard drive into the other drive controller socket (rigt next to where your HD is plugged in now. you can plug them both onto the same ribbon cable if it has enough plugs on it. another cable may need to be purchased.
On the back of the HDD are little black jumpers that can be placed in different positions
If you are putting t\both drives on one ribbon cable then Move the new HDD jumper to be "MASTER" and the old one to "SLAVE". If u look at the hard drive, there'll be a label on top to tell you how to orient the jumpers.
If u use 2 cables and different sockets on t he Motherboard, both can be set to MASTER.

Boot your new Hard Drive and open a File Explorer window
If you are fortunate you may be able to see the contents pf the other drive. Copy as much as you can back to your new drive. DONT COPY THE WINDOWS FOLDER!!! If your old disk is corrupt, it may corrupt your new installtion. Just copy data files if u can and re-install any programs from cd's.
Some data may be corrupted and there may be nothing to recover.
Dont run scandisk on the broken drive, Some files may take ages to copy as the disk may be read over and over....be patient.
Hope this helps and is not beyond your skills of computers!
:)

open the cpu cover then remove dust from allcircuit.
refix ram.but clean dust from allcircuit also from ram and ram slot.
thencheck if problem still then remove cmos cell form motherbord for 15 minutesthen it reset bios.then check .