Does the mother board have a plug in input/output board or does it have on board IDE controllers? Problem could be the board, the cable, the power connector, the jumper on the hard drive making it a master, slave or cable detect.
Could be that the hard drive is toast. Does it even spool up? Is it suspended on springs or in a rubber cradle? How is it Fdisked? to maximum capacity or to the 504MB limit?
When setting up a hard drive you Fdisk it, then format, then load OS (DOS 6.20) then load machine software and parameters.
If the hard disk is bad, replace with a DOM. disk om a module.
George
(Note: The opinions expressed in this post are my own and are not necessarily those of CNCzone and its management)