conked

alrighty! i have an old dead HP laptop which conked off around 2 years ago. It conked off with a bang and after that never got its display back. after 2 yrs when switched on, several indicator lights lit up, but no display. Discussing this issue with several technicians has suggested an expense...

Even though i have 512MB RAM (2 * 256), on system information the available memory shows as 220MB only..is this normal or one of the modules has conked off? is there any tool available to address this?