The interrrupt 47 shows (with powertop) a curious "Description" :[@^EM-W] <interrupt>under a stable Gentoo Linux at a Thinkpad T400 - the BIOS is the latest available. FWIW I attached the output of the command $>cat /proc/interrupts-- MfG/SincerelyToralf Försterpgp finger print: 7B1A 07F4 EC82 0F90 D4C2 8936 872A E508 7DB6 9DA3