I'm a satisfied user of the ASUS PCI-SC200 SCSI controller. This SCSI controller (or more correctly, host adapter) is based on the NCR/Symbios 53c810 chip, which has no BIOS. Because the SCSI controller itself has no BIOS, you need a motherboard with the necessary NCR/Symbios BIOS in order to boot from your SCSI disk. This SCSI controller is inexpensive, and is a good way to get started with SCSI without having to spend a fortune on a SCSI controller.
Note that if you don't need to actually boot from your SCSI disk, for instance if you have an EIDE boot disk, you may still be able to use a 53c810 based SCSI controller even if your motherboard doesn't have the NCR/Symbios BIOS. It depends on your OS and your drivers:
Here is the list of motherboards that I know of with the NCR/Symbios BIOS.
A great source of information about PCI SCSI controllers, including 53c810 based ones, is Patrick Duffy's PCI SCSI controllers for OS/2 list. Equally useful and informative is the PCI Motherboards for OS/2 list; some of the motherboards mentioned above are from this list. More up-to-date versions are available from http://www.os2forum.or.at/english/info/os2hardwareinfo/. The comp.periphs.scsi FAQ has a lot of useful information about SCSI in general.
There are certainly other controllers than the ASUS PCI-SC200 based on the 53c810 chip. However, the ASUS controller is one of the best known, and is also of pretty good mechanical and electrical quality. One of the things to note is that it has active termination on board. Well, had. I was a bit disappointed to see that the last card I bought only had passive termination on board (a resistor pack).
Other manufacturers of controllers based on NCR/Symbios chips (not only the 53c810) are Acculogic, GigaByte, Tyan, DTC, LDP, Tekram and Nexstor. Eric Smith has a nice table showing various SCSI controllers based on the NCR/Symbios chips.
The 53c810 based controllers work extremely well with FreeBSD (my main operating system), and as far as I know they also work well with NetBSD and Linux. I've never tried it with DOS/Windows, so I'll let others speak about this. You may find the Symbios Windows 95 FAQ and the Windows NT FAQ useful.
Some people find it hard to believe that a 53c810 based controller, which is significantly less expensive than for instance the Adaptec 2940, can perform as well. Well, for me it does! I have done quite a bit of testing with the Adaptec 2940UW and the ASUS PCI-SC200 on a 4 GByte Seagate Barracuda, and I found no measurable difference. As always, your mileage may vary.
Some hard numbers: Reading from the raw device, I get 6.8 MByte/s sustained on the outer tracks of a Seagate Barracuda 4, and 5.76 MByte/s sustained over the whole disk. This is measured with lmdd (part of lmbench), on a Pentium-133 running FreeBSD 2.2-960612-SNAP.
That being said, the Adaptec 2940 has a SCSI BIOS (so the motherboard doesn't need one), and it also has somewhat greater flexibility (software selectable termination, etc). The 2940UW has considerably higher bandwidth (40 MByte/s) than the SC200, so if you want many fast disks on your SCSI chain, the 2940UW may be a better choice.
There are now several controllers available based on the NCR/Symbios 53c875 chip, for instance the ASUS PCI-SC875 and the Tekram DC-390U/DC-390F. This chip has a built-in SCSI BIOS, and offers Ultra Wide (40 MByte/s) bandwidth - still at a noticeably lower price than the Adaptec 2940UW.
Thanks to the following for information about motherboards with the NCR/Symbios BIOS:
Michael Campbell <email@example.com>
Dave Platt <firstname.lastname@example.org>
Loren Striegel <email@example.com>
Hartmut Niemann <firstname.lastname@example.org>
Charlie Brady <email@example.com>
David Segall <firstname.lastname@example.org>
Paul Anderson <email@example.com>
Rod Smith <firstname.lastname@example.org>
Victor Hamilton <email@example.com>
Darrell McGinnis <firstname.lastname@example.org>
Stefan Austen <email@example.com>
Patrick Botti <PatrickB@dragonsys.com>
Tonny Iversen <firstname.lastname@example.org>
Bill Bereza <email@example.com>