The Octane fan actually had two speeds, "loud" and "concorde taking off in a hurricane". The high speed fan mode would enable once you put enough expansion car

The Octane fan actually had two speeds, "loud" and "concorde taking off in a hurricane". The high speed fan mode would enable once you put enough expansion cards into the system. there was a pci card cage that would enable high speed and there were 4 proprietary slots where if more than two were inserted the system would get noisy(errr, more noisy). apocryphal story, the graphics came in two sizes and two speeds. the large size was literally two of the small ones on one board but interleaved so while it had 8 mb of high speed rambus memory you could only use 4. anyway, the story goes that there was a very real risk on the large high speed gfx board of the memory getting so hot it would desolder itself from the board. Edit: on the power supply location, I don't think that mattered, sgi's were not like a pc, they have an engineered airflow. air entered from the front and was forced through the compartments independently, on the left was the mainboard, in the middle there were three, bottom to top was the power supply, pci expansion, drive trays. and on the right a mainboard sized graphics card.