A couple of weeks ago, my trusty IBM T22 would occasionally lock up and freeze to the point that the only way I could shut down and restart the machine was to hold down the power button. I suspected that the CPU was getting too hot. I cleaned the fan which wasn't very dirty, and made sure I had good air circulation. The last time it locked up, I was able to power it down, but it is now dead. When I push the power button, the hard drive light flashes and goes out. Nothing else comes up, the hard drive doesn't spin up; the startup screen doesn't appear, no beeps or sound, nothing at all. I suspect the CPU, but before I lay out $75 for a refurbished CPU, I'd like to at least verify that this, and not the PSU, for example, is the problem. Can anyone help me further diagnose this problem before I start replacing parts? My main battery is fine, the CMOS battery reads over 3v open circuit, every thing was working just prior to lockup.

There is 50-50 chance to be either CPU or motherboard. Only way to make sure which one is faulty, is to change the CPU and see what happens. Not advisable. Best thing would be for you to take the laptop to service shop.

Or, you can take a chance, and buy new motherboard, which is really cheap. (CPUs too)

BTW, I think this is 2nd hand stuff.

Thanks for your reply. Unfortunately the links included in your post were for parts for a T21 machine. The lowest price I could find for a replacement motherboard was $207 p/n 26P8098, and for a CPU, $75, p/n 08K3346. One of the repair shops in the Washington DC area that I know to be very reliable is Richard's computer. They want $99 just to diagnose the problem. Now I'm getting close to the price of a new laptop with the same specs, or a refurbished T22. I was hoping for a less expensive alternative.

They claim it to be T22 compatible.