I just picked up one of these boards. Traded a Mackie 32ch 8 buss I got for "almost nothing".
The Yamaha is a rebuildable analog board from the 80's.
I think they were made from 1985-1988.
Sound is head and shoulders above the Mackie. I've got it hooked to a MOTU 828 MKII. Even MP3 playback sounds better going through this board.
Power supply does not need a fan. It never gets hot anyway!