Help! Laptop dead

Hello,
My Compac Presarion V2000 couldn't be coaxed into any response when returning to it after work. No power outages during the day (checked other appliances for tell-tale signs), can't be simply a power supply problem either as I have a second, back-up supply that also can't breathe any life into the machine. In recent weeks, the screen started to show some instability/flimmer and go white at certain positions or angles but this usually got fixed by changing the angle or close and reopen the laptop. It never affected any power issues. But now it's totally dead, no response also from any USB inlets when testing w/ devices. Also no change when taking the battery out to bypass it while connected to AC power. The motherboard already had to be replaced once as I had an instable power connection where the cable needed to be wigled into place and eventually couldn't power the machine anymore at all. Now dead again but without any warning signs (except the flimmering screen but didn't associate this w/ the previous issue). Any one have any idea? Is this a dead motherboard? Would the hard drive also be damaged? P.S. I don't know what type of motherboard is installed - couldn't find the info on the net.