Two months ago, my IBM ThinkPad T43 started to exhibited a very annoying failure mode. It freezes 50% of the time when I popped it out of the docking station. I had to shut down the system by force (hold the On/off button for a long time) and then reboot to put it out of misery. So what happened? What did I do? Could it be software/driver issues or hardware issues?

Several things have changed: I changed the graphic monitor from a 19″ to a Sun 24″ monitor. This could cause the device driver to act weird or the device driver may not like the new monitor. One other thing I had done was to upgrade the SO-DIMM from 512MB to 1GB. I googled to find many people have similar problems. I ended up downloaded a new ATI driver and a special eject software. Neither of them made any difference to resolve this problem.

Being a hardware guy, I just couldn’t believe the DIMM memory should be remotely associated with this problem since the act of undocking simply switch from AC input to battery input. If the CPU didn’t choke, why would memory make any difference? On the other hand, I have solved enough DIMM problems at work to know how fragile DIMM can be – it could be a vibration issue or the memory got put into a different power-down mode that may corrupt the DIMM. Besides, the DIMM I bought was a cheap DIMM from Fry’s. The problem was so excruciatingly annoying that I finally bit the bullet and switched out the new DIMM and put in the old DIMM. Sure enough, the laptop no longer exhibit the freeze problem again. I don’t know what the new DIMM is doing to wreak havoc with my computer but I’m NOT going to be find out and my wife’s laptop now has an additional 768MB (replacing her original 256MB).

Once again, it proves that when it comes to upgrading a computer – make one upgrade at a time. It’s much easier to back out of it. Also, note the changes you make to the computer so you know how to undo. This applies to hardware as well as software.