My x31 is nearly eight years old -- I can't believe how long this thing has lasted, with Win7 no less!
About six months ago, I started having trouble powering and charging the laptop, as if the DC power jack was bad. But I had the media slice and was able to power/charge it through that without any problems. Until yesterday. Now I'm having what I thought was the same problem with the DC jack on the slice. But upon closer inspection, I noticed something very strange -- it seems to power-up and charge just fine, but ONLY when it's in the post-BIOS/pre-Windows phase of startup. I hit the Access IBM button and paused the startup routine right at that spot (by hitting enter), and, surprisingly, it started charging the battery (following the familiar beeps of the p/s being plugged in). And when I plugged the power directly into the back of the laptop, that worked as well. So... it seems that it's NOT power-jack related! But what would cause it to not charge while in Windows, or even in the BIOS menu? Why did this happen with the built-in power jack at a different time than the slice's power jack? I should mention that I'm using a 3rd party battery, but it's in good condition, and I've tried multiple power bricks. Plus there's no unusual heat being generated anywhere as far as I can tell. CPU fan is spinning just fine.
If anyone has any answer or suggestions, I'd love to hear them. Other than this issue (and a few cracks on the case), the laptop works fine.