Compaq laptop CQ57-489wm no video at bootup!

[cmangle]

I have a Toshiba satellite, P505d-S8935 , laptop that won't power up. No video out what so ever. No Bios Post, nothing, and that's on the laptop screen or the VGA out port!
I googled the problem and it seems to be common with this model Toshiba P505d!
One suggestion was to do a hard reset, remove battery, pull AC plug and hold down power button for 30 +secs.
WOW, afterwards this laptop booted up fine, all of the associated lights lit. Asked for BIOS password and then on to Windows Login password and up and running access to everything, working as it should!
I rebooted 3 times with just battery, just AC power and then both!
Fourth time about 15 minutes later, and back to nothing! The hard reset(from above) would no longer work. I removed as many peripherals and swapped out ram modules into different slots and solo as well. NOTHING. Hmmmm.
I put a marble onto the power button and placed battery onto it and let it sit over night with the power button depressed (as in hard reset above) . . . VOILA next morning booted up fine, asked for passwords working OK!
JUST ONCE!
Later in the day I tried again and was jiggling the AC power plug as it was starting/booting and again it booted up fine, JUST ONCE!

Any suggestions? anyone familiar with this P505d series problem? Is it indeed the motherboard? If so why is it so intermittent, and why does the hard reset seem to work . . sometimes?

Thanks Any/Everyone!

[lsemmens]

Could be temperature related, but I don't see how. Probably worth giving it a clean and seeing how that goes, that, at least, is free. Otherwise, Landfill time, methinks. Sadly the cost of repairs may exceed the cost of a new lappy. Don't forget to remove the HDD, you could put that in an external enclosure and use it as a spare drive.

[Philquad]

how hot is it there, the roughest trick i even seen (but it worked)

wrap the lappy in a big towel, leave it with power connected, turn it on, leave it for a hour (in a fireproof place lol)
then try to restart it, why, could be bad solder joints & the heat is just enuf to make the connections work
sadly, it wont fix it, but it rules it out, maybe even put it in the sun for a bit

[cmangle]

Heat might be an issue if it ever started up but it doesn't even boot. When I do the reset (and when/if it works) there is no electricity applied so logic would/might say there's no heat buildup!

When it does boot up and shows a BIOS and LOGIN screen, there are a series of lit icons on the right under the POWER ON/OFF button that DO light up .

When it does not boot up and shows no video at all, none of those icons are lit (light up!)

Normally the circular file is where it would go, But i found one source for a replacement motherboard for $129.00 USD.





Even if there was a fan error causing overheating, BIOS usually boots up and a screen message says FAN FAILURE!

I also looked for evidence of liquid spills on mother board that might be causing shorts, none found!

[cmangle]

Also notice that this is a Toshiba Satellite P505D and not the Compaq CQ57 in the title . . . I was pretty tired when i posted, only to realize later the problem child was Toshiba . .