As to the original subject of this thread, I can't really say what is typical, but the only time I have experienced the blinking curser is when the MBR is missing or corrupt. Usually, for me, missing, after a back-up image has been restored, or a drive cloned. But, I have never seen it happen repeatedly as you have. It sure seems to me that this is what is happening to you, but I don't have a clue as to why. But, next time it happens, try restoring or repairing just the MBR, instead of re-imaging the drive, and see what happens...
By restoring or repairing the MBR, do you mean booting with a W98 and riunning FDISK /MBR, or booting the IBM Thinkpad recovery restore diskette and letting the IBM utulity do its thing (getting back an F11 prompt by rewriting the MBR)??
I've already tried that. No help.
Is there a windows XP FIXMBR routine that might help? I finally got a full XP installation CD, but don't know how to get to that. That may work, but again, i need to find out how to get to it.
As to the cause if it is a southbridge, is this an internal failure in the chip itself or is it de-soldering because of poor heat cycling and/ or stress due to excessive flexing? T30s are much more rigid than T4x and should have less issues due to flexing, however nothing is immune. If it is Southbridge then it is with at least two different machines, and it is ONLY doring something to the HDD, no errors anywhere else with the machines. Plus, putting the drive in as drive D: shows all the files intact.
Recovery is straightforward, but tedious, and its getting annoying.