The System Accelerator (MH032, SysAxe) is the SCSI card used to expand the original Pro Tools system to 8-, 12-, or 16-voices (an Audio Card and Interface is required for each 4 voices).Check the following socket locations for current revs (an ink dot means the PAL had been revised but not relabeled):U17 should be 200137-003. U19 should be 200134-003. U20 should be 200132-003. U37 should be 200 139 004 or BUSC B06. U22 should be 200140-001 or ROM v1.0.Some SysAxe cards may also require a "resister pack" modification that can only be performed at GMR. You can identify one of these by examining the back of the card to see if a very small "surface mount" resistor has been soldered on the non component side of the board opposite U18. You will have to look very closely to see this as it is probably less than 2 ml long.