Dusted off my Xbox for the kids today - powered it up, it defaulted to MS dash and prompted me for the date and time (good thing, I recall the nightmare of endless loops last time)
Set the date, time, played a little Dance Dance Revolution on the native bios with the DVD-Rom (original media)
Expected to power the Xbox off, hit the eject button, and boot into Xenium/EvolutionX or whatever I last had installed on the dash... but only get the stock MS dash, and no signs the modchip is functioning.
Pulled the torx screws (had to find my screwdrivers) and opened it up. Modchip is installed on LPC header with single wire soldered to the topside of the board. Re-seated the modchip since I was in there, closed it all back up, hooked it back to the TV... still nothing but stock.
Most likely cause of no-mod-signs-of-life?