C2D again, this time the
MacBook Pro 4,1 (in my case with 6GB RAM, 17" glossy LED backlit screen), boots Sonoma just fine. Sound works, backlight control works (!), mouse&keyboard work (so USB1.1 seems fine). Wifi & BT do not work (despite having a previously air-drop and handoff capable replacement module in the miniPCIe slot).
Oh wow, and just while typing this I noticed that the old iSight camera also works with FaceTime. Frame buffer shows all of the 512MB of the 8600MGT. No GPU accel, though - as to be expected at this time.
So,
@roysterdoyster, here we might have an extra life with our machines!