I have an x230 with the additional 19+ slice battery. I have noticed over the last couple weeks that several times when I have disconnected the power cord from the slice, while the slice is attached to the laptop, the system unexpectedly reboots. This does not happen every time, only maybe 25% of the time. The system then boots up fine, and will run from the slice battery.

Has anyone seen this before or have any suggestions? It is really frustrating because the system goes down hard, and I loose anything unsaved.

Thanks for your help.

I have seen this before with other ThinkPads. In my case, it was on really bad on a Z61 and I've also had it occasionally on T520s that I own.

I believe it was determined to be defective grounding in the power adapter connecter at the mother board and a new mother board (planar board) fixed it.

The Z61 was very bad. I sent it to some Lenovo engineers in Raleigh Durham who put it in a electro-static discharge room and found a design defect. Although the machine was several months old by then, Lenovo Direct Sales gave me a full refund and I bought a T61p which I still use.

Contact EasyServ 1-800-426-7378 and see what they say.

Barry in Sheridan, Wyoming.