Compaq cq57 black screen

Test all leads that attach to your hard drive including electrical extensions,IDE,SATA

the leads from your ((motherboard to your hard drive)) make sure they have secure dust free connections and are not faulty or just replace them they might be faulty

make sure all leads that are attached to your drives dvd\cd 3 1/2 inch floppy have secure connections and are not faulty even the electical extensions

even something as small as an electrical fan and its lead can cause you problems or just replace them they could be faulty a computer needs all electrical power and data to continue through every working device and to have an end so any faulty leads will end up with a computer error

make sure your graphics card is securely seated with no dust built up or in the socket

if you remove your graphics check the socket to make sure its dust free

restart your computer then reinstall it this should activate found new hardware wizard

hope this helps you