A few silly questions for you of my own.

1). Does you Card show an Error under device manager? If so, what is the error?

2). Some of the newer PP cards dont directly show the address, you have to go under Device and look it up there, sometimes it
may give you 1-3 address Ranges, ususally the 1st one is the best, but, if your already using that one, pick the start range address
of the next range, and retry.

3). Stupid thing to check, but, you DID check the Enable box for the inputs you want to use correct??, and if you PP port is Bi-Directional, and you checked use inputs 2-9 make sure your inputs are in legal acceptable ranges depending on that selection.     

4). The PCI slot it self may be bad, Try you new card in the slot you already have your known working card in, once you plug
it into where the working card was, relook up the address, it may have changed, on your port 1, change the address if neccessary, to what the new card address is.    If you swap the new card into the old cards slot rechange the address (if necc.), and it doesnt work, then try another Brand  "Lava Soft" has know working PP cards.

5). If the above doesnt work, and you have tried other PCI PP cards to no avail, then a more realistic choice may be to buy a Mod Bus board from:  Peter Holman, or Aurturo Duncan, and bring in or out a crap load of I/O.

NOTE: If you goto a NC Pod then everything goes to the NC pod.............

Scott

Thanks poppabear, this looks helpful. I'll only get a chance to run the Mach3 computer again later on, so  I can't try anything just now.
The point about checking "use inputs 1-9"...  I don't have that checked but I only need 2 more inputs, so I was planning to use 10 and 11. Do I still need to check the "use inputs 1-9"...?

No you only need that enabled if you are planning on using 2-9 as inputs. Another thing you might want to consider is the SmoothStepper.
Hood