If anyone has ever tried to run a 2091 Hard drive card on a Amiga 500, you probably know that there are some issues with doing this. But the A2091 is probably one of the easiest HD cards to find for the faithful amiga.
This is a step by step instruction on how to make this work correctly.
DISCLAIMER: I Am NOT responsible for you screwing up Your amiga,
2091 card, Or anything else for that matter. you do this at your own risk
1st off you need an adapter card. The spirit zorroII 100Pin to a500 adapter is a good one, but it's setup at an angle so the 500 has to be raised up
But this is not the major Problem. a couple of the right sized two by fours under the amiga will take care of this.
The bigger problem is Setting up the card so It can run properly WITH Removable media.
from here you need to have at Least the 6.1 Roms in the 2091 card. 7.0's are preferable. You can get new 7.0's HERE
Next is your Hard drive Unit ID. The 2091 is picky and in order to run removable media without screw ups you MUST
set the Hard drive SCSI ID to 6. Nothing Else. All Removable media is set to a lower number. I know this is backwards from the norm but it will solve your removable media problems for the most part (CD drives, Zip Drives, Etc.)
next is the reset problem. You must run a jumper wire from pin 94 to pin 53 on the 2091 card. this will enable the 2091 to receive a Reset signal when the Amiga does a warm Boot (Ctrl-Amiga-Amiga or Program Soft reset)
That's it everything should work fine from here.