IBM Thinkpad T42 - stops responding.

This is a nice lite laptop, IBM is one of my most recommended laptops. It has aP4 1.7Ghz Processor, WiFi, its a thin laptop and one of the most widely used for business. This one has a problem with the motherboard, after you start it but touch it in the wrong way, it powers off. Unfortunately it is already out of warranty. I will try to re-souter the AC Port, if this does not work then the motherboard will be replaced. I will keep you posted.