dell mini 10v shuts down even in BIOS mode, even without hard drive

[gugun khongsai]

i have dell inspiro mini 10,my screen doesn't work. So using vga cable connect to my monitor i can see it starting up in my monitor. what i am really concern about is after exactly two minutes after startup it shuts down its self. I tried cooling using cooling pad doesn't work. Tried changing the thermal compound since its a bit old doesn't work. So i think that its not an overheating problem. Then i tried diagnostics in BIOS but before it can finished the laptop shuts down within two minutes.
I recently install windows xp.
Took out the hard drive check it in other laptop, it works fine. It still shuts off without HDD after sometimes of displaying no OS found.

I cant short out whats causing my laptop to shut down.

Please if some smart guys have any suggestion..
I would be purely thankful to try out.

 

[Laptop_Nerd]

It's your motherboard which is failing already. To back up this theory try this last troubleshooting step. Remove the battery off the laptop then plugin just the AC Adapter then turn it on in BIOS, if it shuts down again clearly it's the motherboard. Last thing you want to try as well to re-seat the RAM, remove the RAM off for couple of seconds then put it back in then power it on.