powersource issue...?

[TheRedFox]

So, recently, my laptop (IBM Thinkpad X31) has had issues where it will randomly turn off, and not be able to turn back on, in the past I have been able to get it to turn back on just by taking out the keyboard, and putting it back in, or occassionally taking off the whole laptop top. it also happened fairly infrequently, but this last time, it would not start working from just that. Because of this, I waited about a day, and then dissassembled the whole thing (took out the motherboard). I was pleased at how easy it was to take apart, although I'm left with a rather suspicious piece of metal, and not sure where it goes, but I digress. It is currently working, but for how long? I don't know. any ideas? if the only possibility is getting a new mobo, then can somebody tell me what price I could expect for an X31 mobo (preferable 1.4 - 1.7ghz)?