I actually have a W520 that I'd like to continue to use. (That keyboard, plus a surprisingly decent display panel for Lenovo.) I hadn't heard of this problem,

I actually have a W520 that I'd like to continue to use. (That keyboard, plus a surprisingly decent display panel for Lenovo.) I hadn't heard of this problem, so thanks for the heads up! I'll be very planful and sparing in my BIOS config access/writes. I think CoreBoot has made it to some if not all of the -20 series. I wonder whether it would make any difference, although I can't see how if you're still writing to that storage.