Compaq Presario 1700 Laptop screen flickers and...

Question

When setting idle in bios setup after a while the laptop screen goes black and seems to be locked up. I can boot it up to install XP, but after a while about half through the install screen starts to flicker then goes normal then will flicker until finally either goes black or to the Compaq logo screen and seems to be locked up. I can hold power button and power down though??? What is up with this thing. I did take keyboard loose and fan comes on at boot up and then turns off and never seems to come back on before it locks up or whatever.