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My 8086 Deskpro is on its last legs.....Upgrade time!

Installed the ATI VGA Wonder XL and connected a old LED svga monitor and ran the ATI tests.

Passed with flying colors.

Need to test it with the original amber Compaq monitor next.
 
Did quite a bit, I have forgotten how amazingly flexible the ATI Wonders are. I can display just about every video mode out to a vga monitor.

I can display mgs, cga, vga, Hercules, ega and some others.

I monochrome I can choose white, amber or green.

Tons of option and all through software.

I installed Compaq DOS 5.0, I have never really been a fan of it.

I think tomorrow i'll install compaq 3.31 and maybe qemm.

Also I played around with the jumpers in just about every combination and only two acually did anything, there are two that if you remove either or both the board just will not boot. The ones labeled freq did nothing.

The cpu always ran at 25Mhz.

I really need to find a manual or at least something with the jumper settings.
 
I went ahead a found Compaq DOS Ver 3.31 REV G disk images and dug out some old 720K floppys.

Installing now.

Still not mounted anything in the old case yet, still configuring everything in the generic AT case until its mostly like I want it.
 
Little update.

The motherboard is still in the generic AT case since I'm still tinkering with it and thinking about a mounting solution to mount a newer board in the old case with out any or as few mods as possible.

I figured out the pin-out on the secondary keyboard header then I used a PS2 connector and wire that I found in my pile of stuff. It mounts to a slot bracket and I think it was for a PS2 mouse for one of my other motherboards from my pile.

It had the perfect matching connector to fit the motherboard and all I had to do was rearrange the wiring order.

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Booted up and it works!!

Thought about using that PS2 connector in place of the original AT connector at the front of the case but I would have to make up a bracket to make it fit. I think I will just cut off the PS2 part of the wire connector and just solder it to the original AT connector on the case.

I have PS2 to AT adapters already so I could use either and still keep it looking original.

Also found a set of Compaq Dos 4.01 image files and installed that just for the heck of it since I never used Dos 4.01, went from Dos 3.31 to 5.0 then to 6.22 and did like most did back then and kept running 3.31 until 5.0 came out.
 
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Hi,

Looking at the OP, I see you were using a 16 bit MFM controller. In another thread on this forum I was told that 16 bit controllers will not work in 8 bit slots which I thought this computer had. So, I am curious what controller you had and how it fared.
 
Hi Klee, I have a Compaq 8086 motherboard, Assy No. 000364. and a matching power supply. I bought the motherboard on Ebay as part of a collection boards that would fit my IBM 5150 A. I just bought a power supply for the Compaq with the intent of making it the Compaq motherboard work. Recently I bought a matching power supply that seems to work properly. I put power to the motherboard and it showed no signs of life. And then it promptly popped two tantalum Caps. my heart is not really into this restoration. If you are interest in the motherboard and power supply private message me.
 
A little update, I lost my then job the day after my last post in this thread due to covid killing business. Went on unemployment for five months so I used most of that time rebuilding my middle daughters car, engine, interior ect.

So this project started going down the priority list pretty fast.

Then started working again, lots more hours, then found a much better job making 25% more with less hours and much closer to home.

Bought a 3D printer and ended up going down that rabbit hole so that ended up being my main hobby for over a year.

During all of that I made a little progress on the old Compaq.

Found a cool adapter from a guy in Russia to adapt my original keyboard to ps2 that will work with the 486 board.

Also found a 32.000 Mhz quartz crystal to be able to run the cpu at 16 Mhz.

Lots of testing made me realize that would be the slowest practical speed that board will run and should work fine for my uses.

Originally purchased the 3D printer to print an adapter to adapt the case to the baby AT board.

The compaq is still not on the top of my priorities list at the moment but I found an almost new looking 286 deskpro motherboard that I will try out and if that does do the job then i'll put the 486 board in another case.

The 286 board is as is and the seller had no way to test but it really looks mint and i'm hoping it does work when I get it in a few days.
 
Hi,

Looking at the OP, I see you were using a 16 bit MFM controller. In another thread on this forum I was told that 16 bit controllers will not work in 8 bit slots which I thought this computer had. So, I am curious what controller you had and how it fared.

I only use the 16 bit MFM controller to use newer 3 1/2 floppy drives since all the floppy circuitry goes through the 8 bit portion of the 16 bit card ,so it lets me boot off a 720kb floppy and use 2M-Xbios.exe to read and copy 1.44 mb floppys.

This link describes it better than I did. http://www.minuszerodegrees.net/2M-XBIOS/2M-XBIOS - 1.44M as B.htm
 
Hi Klee, I have a Compaq 8086 motherboard, Assy No. 000364. and a matching power supply. I bought the motherboard on Ebay as part of a collection boards that would fit my IBM 5150 A. I just bought a power supply for the Compaq with the intent of making it the Compaq motherboard work. Recently I bought a matching power supply that seems to work properly. I put power to the motherboard and it showed no signs of life. And then it promptly popped two tantalum Caps. my heart is not really into this restoration. If you are interest in the motherboard and power supply private message me.

Sorry I have not replied sooner and thanks for the offer but i'm wanting to try the 486 or 286 options mainly for reliability for now.
 
My 286 motherboard just came in, very clean and no obvious problems. It has a 286-8 cpu. Not sure how much ram 2048k?

Pretty pleased so far for a $15 motherboard.

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Good thing when I got my 8086 Deskpro when it was new they gave me these with it instead of the 8086 version.


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Looks like the 286 motherboard is the "COMPAQ COMPUTER CORPORATION 286 DESKPRO 286 (VERSION 2)" on Stason.org's site.

Dissembled the Deskpro enough to remove the 8086 motherboard and now I am comparing them.

EiRVOTP.jpg


Looks like the 286 motherboard does not have a header for the speed LED, manual says it uses beeps instead.
I was hoping I could keep it but would defiantly would lose it if I go with the 486 board, but beeps are ok and maybe I could repurposed the LED.

Well getting ready for the smoke test. LOL
 
Passed the smoke test, no pops or smoke of any kind.

Power LED on the motherboard lights up.

4SxRX0j.jpg
 
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Plugged in the video card and connected the monitor and it test's the ram and gives a keyboard and other errors since nothing else is installed.

Just wanted to know if it would post.

Looking good so far.

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Can't get rid of the 301- Keyboard error.

Tried three keyboards, two original Deskpro ones plus a generic AT-XT switchable keyboard.

Steady beeps until I pull the keyboard plug out.

Got rid of the security lock keyboard error, Stason.org has a couple of errors in the listing for the jumpers. J119 and J115 are swapped.

Tried reseating the bios and keyboard chips.
 
Looks like the #5 keyboard pin, the +5v pin, shows zero volts.

So i'll take the board back out and give it a look over to see if I can find any damaged traces.
 
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Did a quick hack, desoldered the #5 din pin wire going to the motherboard and ran a +5 wire from a molex connector.

No more error and keyboard works.

Need to do a more permanent fix directly on the motherboard.

Next is to install a floppy drive controller card and floppy drive.
 
It boots!!

Only installed the minimum hardware so far and ran some tests.

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Found the issue with the 286 motherboard, the pico fuse F2 is blown. Thats the fuse that protects the keyboard +5 volt line.

The second pin from the bottom on the J116 connector is what supplys the +5 to the keyboard. It goes to component L4 then the trace goes to F2 fuse.

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Naturally I do not have any pico fuses, the 8086 motherboard uses much easier to change glass fuses.

I found a pack of fuses on Ebay, older ones that are a close match and also rated at 5A like the two on the 286 motherboard.

So no running a repair wire needed to fix it, but I will have to wait a few days on the fuses.

This is one of the many reasons I really like vintage computers, much easier to troubleshoot AND fix than newer pc stuff.
 
Replacing that fuse did the trick. No more keyboard error or needing a +5v jumper wire.
 
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