Compaq Deskpro XL 590 - Pentium Workhorse

I recently acquired two Compaq Deskpro XL 590 computers from Free Geek Twin Cities, the pair were labelled as a Project PC, and sold at an enticingly low price.  I was pretty excited to see this because I'd recently damaged my Epson Pentium 75 machine, which was a favorite in my Retro Computer collection, and one of the first that I'd acquired.

The Compaq PCs were in pretty rough shape, as you can see here...

This is an interesting system, it's got a processor on a slot but it's not a passive backplane computer.  There's quite a bit of logic on the mainboard, including; audio, SCSI, IDE, and Ethernet.  The CPU and RAM are on the processor slot, which is almost a full length card.  Modern Classic on YouTube recently did a series of vides on this hardware which you can find here, here, and here.  He started out with a 486 and upgraded to a Pentium 100.

My systems are a Pentium 90 with 16 MB of Built in RAM, these systems have two PCI cards slots, and the rest are EISA slots.  I've never had an EISA system before, so that was an interesting aspect of this build. My goal for this machine is to get Windows 95B running and have a boot menu configuration for DOS gaming or for starting up the Windows 95 GUI.

I had quite a few interesting challenges getting this computer going.  The first was the BIOS setup program.  The BIOS setup program for this computer shipped on Floppy Disks, and can be installed into a small partition on the hard drive, but as with most recycled computers, these machines shipped without a Hard Drive or any floppy disks or documentation.  So,  I started Googling around and used the Wayback machine to figure out what the last set of drivers for this board were.  Having this information was only the start of the struggle, since HP has turned off the FTP site where they had been hosting the old Compaq Softpaqs for many decades.  I asked for and received some good advice about locating these files on the Vintage Computer Forums.

One of my goals for the system is to use it as a Disk Imaging system with a Go-Tek floppy drive emulator with FlashFloppy firmware loaded on it.  I have a couple of these, one lives permanently in my pentium, and the other is a "floater" Go-Tek that's used for building and testing systems.  Using the Go-Tek, I was able to convert the odd Compaq Softpaq Executable files into the more useful IMG Disk Image file format.

I have collected up the drivers I needed to build a Windows 95B machine, and I will link the file here, this includes:
System Diagnostics SP16085
System Configuration Disk 1 - 4 SP6144
Firmware Update (Final 4/7/1997) SP3642
Matrox Millennium PCI Video Card Drivers for Windows95 SP2754
Onboard Ethernet Driver SP1649
Onboard SCSI Driver SP1664

Once I had the disks needed, it was time to start the build.  I wanted to use Compact Flash media for the Hard Disk Drive, but I had no end of problems with a couple of off brand devices that I tried, so for now I've defaulted back too a 6GB Quantum Fireball IDE drive that I had in the parts bin.  The System Configuration utility was able to recognize the drive and startup without error.  Once the System Configuration utility is able to start without error, if there's a blank drive it will offer to install the System Configuration into a partition on the Hard Drive, which I did for convenience.  At that point you can Fdisk the rest of the drive and setup your partition for Windows 95.  This part of the install was normal and painless.

I've moved all the goodies from my Epson computer over to this one.  I've added 128MB RAM, a 52X CD-ROM, a Go-Tek, a newer ISA SoundBlaster 16, a 3Com 3C905C Fast Ethernet card, and a Parallel port Zip drive to use for "Sneakernet".  The case cleaned up pretty good, although it did have some paint missing on the corners...

I'm quite happy with how this machine has turned out.  I still have quite a bit of tweaking left to do to get all my DOS games back up and running, but that is a big part of the fun.  It's great to have a running Pentium class machine back in the stable!

Here's the machine running Internet Explorer 4.0 and using the excellent new FrogFind.com search engine for Retro Computers from Sean at Action Retro...

Next, I need to get the Boot Configuration Menu going, I'll probably copy something from Phil's Computer Lab's MS-DOS Starter Pack.  Also, I've ordered some Industrial CF cards to try again too move the Hard Drive over to Solid State media, but in the meantime, this machine should be tons of fun.

My first CP/M Computer

A few weeks ago an intriguing post popped up on Craigslist.  It was for a CP/M computer that someone here in the Minneapolis / St. Paul Metro area had built up from the board level in 1983.  I believe the builder re-used a piece of old test equipment as the Chassis, and perhaps the power supply that was in the Chassis as well, but the computer itself is a Megatel Quark 100 computer.  This was a Canadian firm.  The computer is a Z-80 based system with 128K of RAM (64K available to CP/M), and two Teac 360K floppy drives.  (I'm still not sure what the formatted capacity of the drives is, since I'm a CP/M newbie.)

At some point the previous owner had recycled the Monitor.  I don't have an MDA / Hercules compatible monitor in my collection, so I ordered and waited for an MCA2VGA to arrive from TexElec.

Once I got the video adapter and a 9 pin male to 9 pin male straight cable, I was able to fire the machine up and test it for the first time, it boots and runs well...

There appears to be an issue with the Horizontal Sync timing on the MCA2VGA adapter, as the last few columns of text on the right hand side are cropped.  Also the video is compressed vertically too about 1/2 of the height of the screen, so I'm not sure what's going on there.  The manuals for the Quark mention specific horizontal refresh timing, but I'll have to dig in on what the timings are supposed to be for MDA / Hercules in order to understand why this isn't working on MCE2VGA.  I'm also on the lookout for a period correct monitor.

The next challenge was the Key Tronic foam and foil keyboard.  Several of the keys were not working...

I've restored a similar keyboard before on my Compaq Portable from the same year, and once again TexElec came to the rescue with their Foam and Foil replacement pads.  Waiting for the pads to come in gave me the opportunity to take the board completely apart and clean the housing and keycaps.  After replacing the pads and re-assembly, the board is working like new, although there's some wear and tear...

I'm quite happy with how this turned out given that the keyboard is over 35 years old!

The next challenge was that the builder of this system mentioned to me that the BIOS is on a Floppy Disk.  The computer won't boot at all without the customized, appropriate BIOS for the peripherals that are wired to this specific build of the Quark.  This left me with a nagging fear that as the floppy disks fail, I'd loose the use of this classic computer.  I'll write a separate bLog article about my new SuperCard Pro Disk Imaging setup, but too make a long story short, I was able to image and restore Bootable CP/M disks for this machine, and capture and archive all the disks that came with this system, so that is a relief.

That wraps up the story so far for my first CP/M computer.  It's working well enough that I can dive in and start learning about CP/M, the precursor operating system to DOS.  There's alot of good information online, and I'm planning to start with "The CP/M Handbook with MP/M" by Rodney Zaks.

On my To-Do list for this computer:

Find an appropriate monitor that can be adjusted to show all the text, or determine why MCE2VGA isn't displaying the image correctly.

Find a Go-Tek equivalent for 360K 5 1/4" drives so that I can replace one of the floppy drives with a solid state drive.

Please let me know if you have any suggestions for me about this computer, or any questions, Thanks!

My newest Apple, the Apple IIc

I've recently acquired a "new to me" Apple IIc.  A friend of mine who is also a retro computer enthusiast was keeping an eye out for me, and a friend of his was looking to keep their families Apple IIc out of the waste stream, so this was a win for everyone.

This lot included the computer, a carrying case, floppy disks, and manuals from the period.  I have a fascination with these manuals, and I'm currently about a 1/4 of the way through the Owners Manual shown on top of the computer here....

I didn't want to power the unit up till I'd done some preliminary checks and cleaning, so I started by testing the mouse on my 512K Mac, it is partly working, but there's something wrong with the Vertical encoder, as the mouse will go up but not down.  I spent an hour or two opening that up and trying to identify a problem, but I was not able to identify a broken connection, or dirt on the encoder wheels.  It's possible the IR LED or phototransistors are no longer working, and this is a repair that I have not yet been successful with on old mice that I've worked on.  Let me know in the comments below if you have any ideas or suggestions about resources for mouse repair.

I took the computer apart to check for condition, it all appears normal inside, not too dirty, although I did a through cleaning on the outside, and a bit of cleaning up of dust on the inside...

In addition to cleaning, I checked for leaking caps, and also took the drive cage off enough to clean the drive read / write head with rubbing alcohol.  I also checked the voltage of the external Power Supply at the plug, and it was reading good.

After putting it back together, the computer works as expected right away...

I checked the ROM version at the BASIC prompt, and it's ROM version 0, so SmartPort support is included (there's also a sticker showing a 3.5" floppy disk above the drive port on the back).  So, using FloppyEmu in SmartPort mode, Total Replay works, which is awesome!

Since I didn't get the matching 9" green screen with this computer, I paired it with an Apple IIe Composite Color Monitor, and built a little two sided stand for the monitor that still allows access to the floppy disk drive on the right side of the machine.

So, the Apple IIc takes its place in the collection both as an excellent gaming machine and as a disk imaging machine using FloppyEmu and the built in 5 1/4" floppy should I need to make disks for any of my other Apple IIs.

Remaining tasks for this computer include the mouse repair mentioned above, and repairing the Kraft KC3 joystick.  I'll try to buy another KC3 on eBay in order to harvest a potentiometer out of the stick too repair this one.  This stick was made for so long and in so many variants that not all the parts are interchangeable, so I'm trying to find ones with the right FCC ID hoping that the potentiometers will be interchangeable, as these are no longer being manufactured.

And finally, the case plastics have yellowed.  Perhaps when summer comes in Minnesota, I'll add this computer to the list of computer cases that need retrobright treatment.  The case did clean up pretty good, so I'm considering just leaving it as is.