>get a cheap Adaptec PCI controller, since Adaptec is the standard in
>compatibility.
Back when I was forced to attemp to deliver services on x86 hardware, I
had various flakiness with 2940's. Less, to be sure, than with the
@#$@# Buslogic 946's that I was forced to use before, but still hassles,
especially with more than one in a box. When I tried a DPT controller,
everything worked perfectly. I wouldn't buy anything else for x86
hardware.
As for speed, there's drive throughput, and there's transfer rate. The
transfer rate can indeed be an issue -- slow transfers to the tape drive
mean more bus occupancy, which means that there's more contention for
disk access. This was especially bad eg. on SunOS 3.x, which didn't do
SCSI disconnect/reconnect. Writing to a tape on that platform pretty
much hung the whole machine if it had a SCSI system disk.
So, if a given tape drive does fast and/or wide transfers, having
matching support in the controller and cabling can make a difference.
