T61p fan starts then stops, no video output

[MooNWalker]

When I plug the power supply in my T61p it turns on immediately, keyboard lights blink as if it initialized the keyboard, and then it just sits there with AC and power lights on, no video neither on built-in LCD panel nor on external monitor, no POST sounds, nothing. I tried to unplug both AC and battery and hold power button for 10-15 seconds to discharge capacitors, didn't do any good. Pulling out all drives and cards didn't help either, and there is still no beeps even after removing RAM, though I know speakers themselves are good (checked them with other machine). When I tried to turn it on with keyboard open (making sure I don't short out anything on MB) I noticed that fan starts when I plug in AC and then stops as soon as keyboard lights blink.

Can anyone give any insights as to what might be the problem and how can I fix it besides replacing the motherboard?

[zern]

I had a similar thing a few months ago.
Plugged power cord in. Pressed power button (not immediate start like yours). Lights came on. Then nothing. No POST, no display, no beeps, no fan.
The reason was, when I opened it up to clean the fan I accidentally knocked some of the cables loose.
The fix was, I opened everything up and pushed all the visible connectors firmly back into their sockets.
It's been fine since.

[Neil]

..how can I fix it besides replacing the motherboard?

That may well be the only option. A system board that doesn't even beep when there is no RAM installed, is almost always a gonner.