I guess you mean an optical drive, and I guess it doesn't matter. You can find faster IDE drives (even servers used to have IDE ports for CD/DVD), but some games won't work with 48x IDE drives. Also, keep in mind that anything related to SCSI is crazy expensive.

If you're talking about HDDs, SCSI might be faster because of faster rotation speeds (don't get wrong... IDE HDDs can have more peak transfer rates, but SCSI perform better at sustained transfer rates). But (unless you're building a server) I'd still recommend IDE because is easier to find good drives and they're cheap.

Hi Zup the drive im thinking of using is a Scsi CD rom drive that I already have but the only thing holding me back is that the plastic for the drive has gone a bit yellow from age its a strange drive in that when it ejects the caddy for a cd the whole face plate is the caddy, when you say it doesn't matter does that mean both the Scsi Cd drive and the Dvd drive would be the same in performance? I read somewhere from a manual for this drive from memory something about this is the fastest access CD rom drive but the manual was made a long time ago and is probably not current today

Scsi drives were the best for a while, especially in regards to cd burners but for pur cd-rom performance it doesn't matter.
As someone who was using SCSI extensively, don't go there 😀
The controller ads startup time and another driver to load. And then you might think a hard drive might be fine... but these are so loud!

SCSI CD-ROM drive that came with PAS16 was probably double (might be quad) speed. So pretty slow.

There might be an advantage with SCSI CD roms with lower CPU load especially on 486 and below.

kixs wrote:

SCSI CD-ROM drive that came with PAS16 was probably double (might be quad) speed. So pretty slow.

Yes, you're right. The CD-ROM kit came with a CDR-H93MV (CDR-H93), a 2x drive.
See Re: What type of CD drive is this?

(As far as I know, it had its issues with multi-session discs..
In contrast, my father's singel-speed drive LU005 worked fine with them.)

Next question to ask yourself is which is more interesting/Different?
Caddy SCSI drive hanging off the back of a sound card or standard IDE drive?
But for practical use and ease of setup IDE wins easily.

A couple of comments specifically regarding the SCSI controller in the PAS-16:
-It has a max throughput of 690 K/s. This means that it can only really keep up with a 4X or slower drive.
-It uses PIO. This means that it doesn't need its own IRQ, but it will have higher CPU usage and be slower.
-If you use the MAMV1.SYS and ASPICD.SYS drivers from Adaptec SCSI Works instead of TSLCDR.SYS, you can use the CD-ROM drive without having MVSOUND.SYS loaded, which can come in handy.

SCSI in general can come in handy if you have a limited number of IDE ports. I use SCSI CD-ROM drives on both my 486 machines. The drives are a bit more expensive than IDE, but not nearly as bad and much easier to find than some of the more obscure stuff like the Sony or Panasonic proprietary interfaces.