This is sort of a weird resurrection of a year old thread
Was thinking same...
but if anyone is still looking of decent ISA bus bootable SCSI controllers then you can't go wrong with an Adaptec 1542
ALSO thinking the same.
The entire 1542 line are in my experience the BEST in ISA SCSI adapters, if for no other reason than that unlike most other ISA SCSI adapters, it actually seems to properly implement being hot-pluggable.
Back in the early 1990's I was working for a place where one of the clients had pretty much built their entire business around the Compaq portable III using a custom card to turn them into EKG machines. They also had a desktop version for calibration and office testing, but the portable was more popular with hospitals... but they had a problem.
1) Extra hassle of an external parallel drive since the data had to be shipped off for proper analysis.
2) Compaq PC3's were drying up in the supply channel since they were already out of production
3) Next generation information gathering required more powerful systems in both processors and storage capacity
4) The custom card for the PC3 was unreliable and often broke loose in shipping.
But I remembered from the back of Computer Shopper that there was a company selling PC3 style cases -- nearly identical -- but with a full height floppy bay, internal room for a 3.5", and that took a standard mini-AT motherboard... So I got my boss to order one for evaluation, built it up as a 486DX/2-66 with a 1542C, removable SCSI 1 gig hard drive (which was batshit storage for a PC in '92), internal 512 meg for booting and software, and one of the client's desktop cards plugged into it.
Which from the time I showed it to the client to the time I left the company, they bought those suckers like hotcakes. We had several hundred deployed 'in the wild' with pretty much every model of 1542 Adaptec ever made, with zero failures, zero issues, and greatly sped-up deployment. They were just rock solid reliable and even replaced their desktop models.
... and being we're talking about a lunchbox where they would get shlepped around by medical personnel not computer experts, that's a harsh environment where failures should (and typically were) common. See the pile of junk actual Compaq's the client had piled up in the corner. (Always regretted not asking "Hey, could I have a couple of these?")
Though some custom changes I made to the case of the PC3 clones helped with the shipping issues as I took a page out of the PC Jr's playbook, and took some lexan and hot-cut slits into it which was then epoxy'd to the lid. When you put the cover back on it, the slits lined up with the control cards meaning they couldn't lift up out of their sockets during shipping. Was a cleaner solution than going down in there with a hot-glue gun like you saw so many companies do.
If you can find them the 1542CF -- here's an older pic of one from my collection:
Is the best of the best of the best -- with honors -- to come from Adaptec for the ISA form factor. I usually HATE software controlled hardware settings, but the card never failed me, it's auto-detection of other hardware is (in my experience) bulletproof in that it even seems to go "hey, there's ROM here, let's not put our ROM there" and show a "Rom Conflict, check AHA-1542 Address switches" message -- and is still PRE "plug and play" meaning you still retain far more control over it from its ROM than you would relying on the system BIOS to place the IRQ's, DMA channels, and ports.
But if you want to go the old-school jumper route, 1542B is a fine and dandy card that is otherwise identical.
Hell, that 1542CF pictured above is in my 286-20 clone driving a 1 gig seagate right now.... though that drive is probably being pulled to see if it will work with a ST-02 V3.0.0 in a XT clone.
Bottom line, if I need SCSI and have a 16 bit ISA slot available, AHA-1542 or GTFO.