[indy99]

As you've probably already discovered there should be a fan attached to the underside of the graphics board. It connects to a standard three-pin fan header on the system board, but uses the non-standard IP35 SGI fan pin-out.

If your graphics board is disabled due to mechanical failure, if an original O350 rack-style graphics board isn't readily available you should be able to temporarily replace it with a Fuel V12 or V10 until an original replacement becomes available.