View Full Version : Compaq portable 286? Please help

June 23rd, 2016, 06:14 PM
Hi folks, AJ Windmeyer here. 17 years old and a big dos fan. As some may know, i usually work only on GW2K stuff, but i got me a Compaq portable 286 the other day for 25 dollars. The Hard Disk was dead (type 2) so i put a type 33 in my system, and with a new made diagnostics disk tried to change the bios to type 33. but it didn't work, although it was an option in the F1 menu. The system said that 33 was not valid, but the menu gave it there as a option. What should i do?!


June 23rd, 2016, 11:26 PM
Where did the type 33 come from? I guess it can be hit and miss if it's not exactly the same drive as the config disk expects. I'd replace the hard drive with a compact flash IDE drive. I have the same machine, mine has a type 2 hard drive which still works, but for convenience sake I replaced it with a compact flash IDE drive. I set the CF drive to type 25 (134mb) using a 160mb CF card. It's been working very well with that setup. See my post on it here:


June 24th, 2016, 02:04 AM
I seem to remember that Compaq used a different list of hard drive specs to everyone else. So if the drive itself is marked "Type 33" then that probably refers to IBM's "Type 33", and Compaq would have called the same drive something else. The portable is probably trying to use a different drive geometry from what you'd expect, and it doesn't match.

There's a Portable 286 manual floating around on the web somewhere, that should have a list of drive parameters that you can cross-reference with the generic list everybody except Compaq used.

June 24th, 2016, 07:44 AM
I have a Portable II that came with a non-functioning 20mb hard drive mounted on an ISA card. Oldest drive I had available was a 1990-ish 426mb drive, and I got it working with a dynamic drive overlay program specified for that maker of disk (Seagate Ontrack, I think.) I picked a drive number closest to the drive size, then ran the program. It detected the drive, and allowed me to partition and format it to the right parameters. I originally planned to install DOS 3.3 to add authenticity to the vintage of the PC, however I ended up installing DR DOS 7. Incidentally, that was what the OnTrack tool disk was formatted with, and my guess is 3.3 had trouble with DR DOS 7's partitioning.

Funny thing is when I used to buy new hard drives, I wouldn't keep the software provided with the drive. Instead, I'd re-purpose the floppy. Somehow this floppy evaded re-formatting and saved the day!

June 24th, 2016, 05:13 PM
Used to run an executable for my PortableII {called ROMTABLE.EXE} to display the BIOS drive configurations. Available here (about 2/3 down the page):

http://www5.ncr.com/support/support_drivers_patches.asp?Class=pc_library_utili ty

June 24th, 2016, 05:41 PM
Unfortunately "type 33" is basically meaningless. Exactly what brand/model/make is the hard drive?

These are the defined drive types for the IBM AT: http://minuszerodegrees.net/5170/hdd_type/5170_hdd_type.htm
Notice it doesn't even go up to 33.

Here are what some other BIOSes define:

Notice that their "type 33" is different for each one.

From the sound of it, this portable 286 doesn't even define 33.

So you are going to need to
1:determine your drive's actual geometry via make/model
2:determine what your machine actually supports with the above listed utility (unless someone has a Portable 286 rom table dump handy)
3: Either use a lesser value that falls within the C/H/S range for less capacity, or use a formatter with an overlay system as suggested above.

July 21st, 2016, 02:12 PM
Not sure if I missed this, but just in case...

First, by Compaq 286 do you mean a Compaq II or III? What I found below relates to the II

I found this site discussing the details of the Compaq II, including the drive table:

I suppose you can look up the C/H/S of the drive you have and match it to table listed.