XT-IDE vs. SCSI on IBM XT/286

[willmurray461]

My Seagate ST-225 in my 5162 just died on me. I have no idea why. It worked for one second, turned off the machine, turned it back on and it was dead. It kept making this grinding noise as the head stepped through the entire disk, probably trying to find track 0 or something, eventually ending in a 1790 error. I guess I'm not surprised as all of the other ST-225's I've encountered were dead. Anyway, It seems that there are two replacement options out there: XT-IDE & SCSI. At first I thought that I should just go with XT-IDE, as it seems to be pretty popular these days. I had used it before with a 5170, and it worked fine. However, XT-IDE would require a lot of components. First you need to pay someone to burn the ROM for you, and then you need to get a generic IDE controller. After that, since the 5162 doesn't have the empty ROM sockets on the mobo that the 5170 has, you would need to buy a network card to hold the XT-IDE ROM, as well as an IDE HDD, or an IDE to CF adapter for flash cards. I recently heard that the XT-IDE cards are now (maybe) compatible with AT's, but I also heard they're pretty slow. After looking at XT-IDE, I then came across a thread discussing SCSI on ISA machines. For SCSI, all I would need to do is get a SCSI controller (I heard the Adaptec 1542CF is good), and a SCSI drive. I also heard that SCSI is faster than XT-IDE. Anyway, I wanted to know if anyone had anyone had any input. Would SCSI actually be faster? Are XT-IDE cards a good choice for AT's, etc. Help would be appreciated!

[Chuck(G)]

There were some heavily-cached 16-bit SCSI controllers for ISA. An example would be the CDC Fastcache 32. Many others were made. Depending on your system software needs, I suspect one of these would be faster than an XT-IDE.

However, there were also several good ISA IDE cards made--and these would be inexpensive. Some, such as the Promise controllers even have support for larger drives.

[maxtherabbit]

Even without cache, SCSI is faster on a 286, if you use a bus mastering HBA like the 1542. I did a whole thread on it a while back here. Obviously a cached controller would be better

That's being said, I've got a 16bit ROM card in development that you could build for cheap to go the XT-IDE route

[Trixter]

I recently heard that the XT-IDE cards are now (maybe) compatible with AT's, but I also heard they're pretty slow

They are not that slow, especially if they've been flashed with the proper BIOS for the system. However, you're correct that they are incompatible with the IBM 5170 BIOS, so SCSI would be more appropriate for your system. (If your 5170 is running an AMD BIOS, then XT-IDE is back on the table.)

[george]

For how long is your ST225 producing the recalibration sound after spin-up? It could be normal if it is for some 20 seconds. I recommend you to try a low level format and/or media analysis. For testing purposes you can do the format with 2 heads only (10MB). With vintage machines the speed is not important at all...Just get what is easily obtainable. A SCSI is not a bad idea for XT machines provided you can find a controller, for PC/ATs SCSI is just a useless complication.

[maxtherabbit]

If you don't have any IDE card at all, you might just want to purchase one with an integrated option ROM as Chuck alluded to. But I would wonder - if the XT-IDE ROM doesn't work on the 5170, would a 3rd party IDE controller's option ROM work either?

[Stone]

What about a DOM?

[Trixter]

But I would wonder - if the XT-IDE ROM doesn't work on the 5170, would a 3rd party IDE controller's option ROM work either?

It's the XUB specifically that has issues with the IBM BIOS on a 5170, not all cards.

[Chuck(G)]

My first exposure to SCSI on a 5170 was with the WD7000 controller. Good and fast (for the day), but murder to find the right driver for. There are better 16 bit ISA controllers.

I run a 9GB HP FH 5.25" SCSI on a 20 MHz 80386 machine using a DTC 3280. Still works fine, even it that drive is a bit loud (compared to 3.5" IDE drives). Drives 3 floppy drives off the same controller.

ESDI is another, albeit less common, option.

[1ST1]

Why cache, why ScSI? It's easy to get flash based IDE drive solution (CF with adapter), and that's much faster.