Nice setup! 👍 Cool that the hard drive came back to life, was it a 10MB Seagate?

I've seen there are a few apps that let you do a couple of dual monitor tasks if you have both CGA and MDA cards, think Lotus 123 was one of them, what did you try with the dual monitors on this ATI card?

Always great to see another historical machine up and running again

CC-Adam wrote on 2026-06-03, 07:56:

Nice setup! 👍 Cool that the hard drive came back to life, was it a 10MB Seagate?

I've seen there are a few apps that let you do a couple of dual monitor tasks if you have both CGA and MDA cards, think Lotus 123 was one of them, what did you try with the dual monitors on this ATI card?

Thanks!
Yes, it has the original 10 MB Seagate ST-412 in it.
I was just curious to see what happens if VGA and MDA are connected at the same time. There was no motive behind it, only curiosity.
The MDA monitor did not get a signal.
With this videocard it takes a bit of time for the MDA monitor to get a signal. Maybe I will try by attaching the VGA after I have an MDA output.

In the next couple of weeks an FPU (Intel 8087-1) will arrive and thinking of adding a mouse later.
I want to try SimCity, this game can use the FPU. Few games used it in this era.
Stunt Track Racer from 1989 is another one. This being a racer game I might do a "benchmark" with the original AMD 4,77MHz CPU and FPU ON and OFF.
Grand Prix Circuit cannot use FPU and runs quite badly (~7-10FPS), but it is still fun!
Oh, and since the IBM 5151 monitor has a very high persistence the whole game was green smear on this monitor... and this was state of the art back in 1983.
How far we evolved with 1000Hz refresh and 0,1ms response OLED monitors.

Yeah best game playing mode back in the day was to turn your lights off and turn the brightness all the way down on the monitor for less smear.

Excellent, I would like to see Sim City on there! Will it be even remotely playable, even with the FPU? I have a 5160 I might need to give it a try I've been wanting an excuse to dig it out again. Don't have a co-processor for it though (yet!...)

JAKra85 wrote on 2026-05-24, 21:33:

Today I brought it down, did a clean, disassembled made photos, reassembled. Changed the videocard to ATi Wonder 1024 - ISA - 51 […]
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Today I brought it down, did a clean, disassembled made photos, reassembled.
Changed the videocard to ATi Wonder 1024 - ISA - 512KB (PN 109-00095-10).
One of the fastest videocards possible from ATi (28800-5) for this CPU.
This is a 16b ISA working in 8b ISA mode.
The PC Tools program reports only 256KB RAM on the videocard, not exactly sure why that is.
Has both VGA and EGA outputs.
(Tried IBM 5151 monitor and an LCD at the same time, does not work. 😜 )

Hi, it might be that PC-Tools Deluxe from the 80s checks for full 256 KB or less.
256 KB was the full expansion for EGA cards and the base memory for VGA cards.
So the register in memory can't tell if its 512 KB or 1 MB.
Other programs might report "256 KB/512KB" instead.
Merely VGA aware programs do really count the video memory, I think.

https://dosdays.co.uk/topics/Manufacturers/at … vga_wonder+.php

I was just curious to see what happens if VGA and MDA are connected at the same time. There was no motive behind it, only curiosity.
The MDA monitor did not get a signal.
With this videocard it takes a bit of time for the MDA monitor to get a signal. Maybe I will try by attaching the VGA after I have an MDA output.

This works just fine, if two cards for each monitor is used.
VGA and MDA can co-exist, an MDA monitor was often used by developers to see debugger output (SoftICE, Windows etc).
Things is, there are two types of MDA cards.
Real MDA cards with 4 KB of RAM and MGA (Hercules, HGC) cards with 64 KB of RAM.

But because Hercules cards do boot up as plain MDA cards, as well, they cause no trouble.
Programs like Checkit will merely see a plain MDA card in short.
It needs a driver or utility to enable the graphics RAM (Hercules driver disk, msherc driver etc).

If other graphics cards can be used in graphics mode or not is up to the VGA BIOS.
It has to be smart enough to decide if the VGA card makes room for another graphics card.
If it makes room, the VGA card looses some of its video modes.

Edit: Two monitors on one VGA card may or may not work.
I vaguely remember that some VGA cards from late 80s (ATI?) had "auto-sense" and would try to detect the monitor type.

Jo22 wrote on 2026-06-05, 23:12:

Hi, it might be that PC-Tools Deluxe from the 80s checks for full 256 KB or less. 256 KB was the full expansion for EGA cards an […]
Show full quote

JAKra85 wrote on 2026-05-24, 21:33:

Today I brought it down, did a clean, disassembled made photos, reassembled. Changed the videocard to ATi Wonder 1024 - ISA - 51 […]
Show full quote

Today I brought it down, did a clean, disassembled made photos, reassembled.
Changed the videocard to ATi Wonder 1024 - ISA - 512KB (PN 109-00095-10).
One of the fastest videocards possible from ATi (28800-5) for this CPU.
This is a 16b ISA working in 8b ISA mode.
The PC Tools program reports only 256KB RAM on the videocard, not exactly sure why that is.
Has both VGA and EGA outputs.
(Tried IBM 5151 monitor and an LCD at the same time, does not work. 😜 )

Hi, it might be that PC-Tools Deluxe from the 80s checks for full 256 KB or less.
256 KB was the full expansion for EGA cards and the base memory for VGA cards.
So the register in memory can't tell if its 512 KB or 1 MB.
Other programs might report "256 KB/512KB" instead.
Merely VGA aware programs do really count the video memory, I think.

https://dosdays.co.uk/topics/Manufacturers/at … vga_wonder+.php

I was just curious to see what happens if VGA and MDA are connected at the same time. There was no motive behind it, only curiosity.
The MDA monitor did not get a signal.
With this videocard it takes a bit of time for the MDA monitor to get a signal. Maybe I will try by attaching the VGA after I have an MDA output.

This works just fine, if two cards for each monitor is used.
VGA and MDA can co-exist, an MDA monitor was often used by developers to see debugger output (SoftICE, Windows etc).
Things is, there are two types of MDA cards.
Real MDA cards with 4 KB of RAM and MGA (Hercules, HGC) cards with 64 KB of RAM.

But because Hercules cards do boot up as plain MDA cards, as well, they cause no trouble.
Programs like Checkit will merely see a plain MDA card in short.
It needs a driver or utility to enable the graphics RAM (Hercules driver disk, msherc driver etc).

If other graphics cards can be used in graphics mode or not is up to the VGA BIOS.
It has to be smart enough to decide if the VGA card makes room for another graphics card.
If it makes room, the VGA card looses some of its video modes.

Edit: Two monitors on one VGA card may or may not work.
I vaguely remember that some VGA cards from late 80s (ATI?) had "auto-sense" and would try to detect the monitor type.

Thank you for the detailed description!
I set the IBM 5151 monitor aside, takes too much space.
Now only using the VGA with this IBM XT.

I now have other issues, I think it could be videocard related.
I need assistance/advice if and how I can fix this.

1) There is a corruption visible in SimCity. It's a mouse trailer issue, I do not know how to better describe it. 😀
Since I do not yet have a mouse I'm using the keyboard to move the cursor.

2) After 10-15 minutes there is a fuzziness on the screen, it might be PSU related.
When the PC boots everything is clean and clear after a time I see this fuzziness and it gets worse with time.
It is very strong when both HDD and FDD are active (high load). With less load or idle this does not go away.
Also almost all ISA ports are populated.
I'm thinking of changing the capacitors in the PSU for a cleaner voltage. Manufacture date is 1983 week 41. I don't think anyone touched this since. 😀

CC-Adam wrote on 2026-06-05, 20:58:

Excellent, I would like to see Sim City on there! Will it be even remotely playable, even with the FPU? I have a 5160 I might need to give it a try I've been wanting an excuse to dig it out again. Don't have a co-processor for it though (yet!...)

Yes, it is enjoyable even without an FPU.
On the fastest speed it takes between 8 and 13 (it's not constant) seconds to simulate one month on a very basic city. (same city same build, nothing extra added).
The FPU is on it's way, very curious of the change.

System update: Network & Sound added!

I've added one network card (WD8003W) and one sound card (Sound Blaster 2.0 with CMS Upgrade).
Both are set up.

The sound card is tested and working nicely. Waiting for a bracket.

The network card is set-up and ... I could not test it.
Big thanks to Michael B. Brutman for the mTCP apps!
http://brutmanlabs.org/mTCP/mTCP.html
This Half-Duplex 10Mbps card is too slow for my FTTH router to auto-negotiate. 😁
Will set something in the middle and hopefully I can get it working.
Target for the network is to be able to send simple e-mail. Getting and reading is not important, only sending.
Also, would be nice to copy data over network. (not that important)
Now I copy from my main PC to a CD, go to my workhorse PC (486) that has every drive possible, copy data to floppy and copy it to the XT.

From left to right:
Video card
FDD controller
Sound card
HDD controller (MFM)
256KB memory expansion card
Another 256KB memory expansion card
Network card
(one ISA port left for a Microsoft InPort mouse card)
Aaand hopefully my XT will not die from IRQ overload. 😁

The video card looks funny in this 8bit ISA.
Made in Canada 😉

Keep in mind that the last ISA slot on XTs is 'special.'

https://www.lo-tech.co.uk/wiki/IBM_Personal_C … em_Board_Slot_8

You might be better served replacing the two 256k memboards with a modern lotech 1mb card, and putting the inport mouse on slot 7.

The 'extra' memory can live above 640k on a lotech card, and enabled with use!umbs.

Dos cant be loaded high (this IS an XT. No HMA!), but can use the umbs, in such a circumstance.
use!umbs can be found in simtel mirrors, like this one.

http://www.lanet.lv/simtel.net/msdos/memutil-pre.html

wierd_w wrote on 2026-06-16, 20:58:

Keep in mind that the last ISA slot on XTs is 'special.'

https://www.lo-tech.co.uk/wiki/IBM_Personal_C … em_Board_Slot_8

You might be better served replacing the two 256k memboards with a modern lotech 1mb card, and putting the inport mouse on slot 7.

Thanks for the heads up!
I knew from the past that ISA8 is special, however in my mind the ISA8 is the one farthest from the CPU, the one used by the video card. And I was happy I had no issues with "ISA8".

Might not be able to use it after all. In that case something must go, probably the sound card.
The least used in this machine. PC speaker all the way!

I'd suggest a lowtech 1mb card, which removes the need for the 256k cards, and frees a slot.

https://www.lo-tech.co.uk/wiki/Lo-tech_1MB_RAM_Board

It has fancy DIP switches to set which banks in the 1mb space to enable.

This means it can suppliment onboard memory, and have adapter rom region 'holes' set for things like the disk controller ROM and the VGA bios.

The 'unused' adapter rom space can have RAM assigned, and then enabled with Use!Umbs.

wierd_w wrote on 2026-06-16, 21:06:

I'd suggest a lowtech 1mb card, which removes the need for the 256k cards, and frees a slot. […]
Show full quote

I'd suggest a lowtech 1mb card, which removes the need for the 256k cards, and frees a slot.

https://www.lo-tech.co.uk/wiki/Lo-tech_1MB_RAM_Board

It has fancy DIP switches to set which banks in the 1mb space to enable.

This means it can suppliment onboard memory, and have adapter rom region 'holes' set for things like the disk controller ROM and the VGA bios.

The 'unused' adapter rom space can have RAM assigned, and then enabled with Use!Umbs.

This is also a good option, however I would like to stay age/time authentic if possible.
Had a quick look and found this interesting card:
https://www.ebay.com/itm/398068600544
If I upgrade the DRAM chips on it I *might* be able to get 512KB (that is enough for me) and it also has RTC integrated, which XT lacks!

JAKra85 wrote on 2026-05-24, 21:33:

The FDD was also suck. It did spin, but the stepper motor was stuck. WD40 plus some grease on the head rail a bit of back and forth movement solved the issue.

FWIW - if you want to excercise it to work in lubrication- ImageDisk "Clean heads" function works by "scrubbing" heads back and forth - you could use that to work the stepper mechanism.

JAKra85 wrote on 2026-06-16, 21:19:

This is also a good option, however I would like to stay age/time authentic if possible. Had a quick look and found this interes […]
Show full quote

wierd_w wrote on 2026-06-16, 21:06:

I'd suggest a lowtech 1mb card, which removes the need for the 256k cards, and frees a slot. […]
Show full quote

I'd suggest a lowtech 1mb card, which removes the need for the 256k cards, and frees a slot.

https://www.lo-tech.co.uk/wiki/Lo-tech_1MB_RAM_Board

It has fancy DIP switches to set which banks in the 1mb space to enable.

This means it can suppliment onboard memory, and have adapter rom region 'holes' set for things like the disk controller ROM and the VGA bios.

The 'unused' adapter rom space can have RAM assigned, and then enabled with Use!Umbs.

This is also a good option, however I would like to stay age/time authentic if possible.
Had a quick look and found this interesting card:
https://www.ebay.com/itm/398068600544
If I upgrade the DRAM chips on it I *might* be able to get 512KB (that is enough for me) and it also has RTC integrated, which XT lacks!

I've done some digging. It looks like Microsoft's InPort mouse card is designed to be able to operate on slot 8. So, your original plan might be workable after all.

See for instance, the specimen here on The Retro Web, which has the required "Slot 8" jumper.
https://theretroweb.com/expansioncards/s/micr … evice-interface

DaveDDS wrote on 2026-06-16, 21:59:

JAKra85 wrote on 2026-05-24, 21:33:

The FDD was also suck. It did spin, but the stepper motor was stuck. WD40 plus some grease on the head rail a bit of back and forth movement solved the issue.

FWIW - if you want to excercise it to work in lubrication- ImageDisk "Clean heads" function works by "scrubbing" heads back and forth - you could use that to work the stepper mechanism.

Thanks!
I know the program and used it to clean the old Teac 360K drive in my 486. To be able to format and copy data to and from my XT.
I've used the floppy drive on the XT so much the past few weeks that I think the lubrication is very well worked in already. 😀
I copied drivers for network and sound. I copied multiple programs and games.
I had to copy SimCity Classic twice! (messed up, every file was read-only and created issues in game... was easier to just start over than modify attributes on the XT), which is a lot larger that previous (original) SimCity games, around 16 floppies copied just for this game.

wierd_w wrote on 2026-06-16, 22:26:

I've done some digging. It looks like Microsoft's InPort mouse card is designed to be able to operate on slot 8. So, your orig […]
Show full quote

JAKra85 wrote on 2026-06-16, 21:19:

This is also a good option, however I would like to stay age/time authentic if possible. Had a quick look and found this interes […]
Show full quote

wierd_w wrote on 2026-06-16, 21:06:

I'd suggest a lowtech 1mb card, which removes the need for the 256k cards, and frees a slot. […]
Show full quote

I'd suggest a lowtech 1mb card, which removes the need for the 256k cards, and frees a slot.

https://www.lo-tech.co.uk/wiki/Lo-tech_1MB_RAM_Board

It has fancy DIP switches to set which banks in the 1mb space to enable.

This means it can suppliment onboard memory, and have adapter rom region 'holes' set for things like the disk controller ROM and the VGA bios.

The 'unused' adapter rom space can have RAM assigned, and then enabled with Use!Umbs.

This is also a good option, however I would like to stay age/time authentic if possible.
Had a quick look and found this interesting card:
https://www.ebay.com/itm/398068600544
If I upgrade the DRAM chips on it I *might* be able to get 512KB (that is enough for me) and it also has RTC integrated, which XT lacks!

I've done some digging. It looks like Microsoft's InPort mouse card is designed to be able to operate on slot 8. So, your original plan might be workable after all.

See for instance, the specimen here on The Retro Web, which has the required "Slot 8" jumper.
https://theretroweb.com/expansioncards/s/micr … evice-interface

"I've done some digging. It looks like Microsoft's InPort mouse card is designed to be able to operate on slot 8. So, your original plan might be workable after all."

Perfect!
I will try that RTC and memory expansion card nonetheless. 😀

This is the MS mouse I've bought, I think it goes well with the IBM XT. Expect it to arrive soon.

Another operation successfully complete.

In a previous post I've mentioned there is a strange fuzziness visible on the screen and that it might be PSU related.
My assumption was correct, it was caused by dirty signal from the PSU.
I was afraid it could cause serious damage to other components.
So I initiated the two part operation last evening, completed now.

Sorry, no photos.
I'm not a photo making person at each step.
If need assistance contact me and I will gladly help.

Operation "Gut the PSU!" - Part 1
- Disassembly, PSU is riveted in two points.
- Not so easy to take it apart.
- Very-very dirty. More than my mind.
- I had a few "What the hell am I doing?" moments...aaaand continued.
- I've asked my online neighbor at 01:00AM for some heat shrink tubing, what I had was too narrow.
- Once everything was out I was like: "Shit, what now?", this PSU is way too complicated. It's not just a simple capacitor change anymore.

Operation "Gut the PSU!" - Part 2
- I have multiple AT PSU units. Took the one I was most confident with; all caps Made in Japan.
- One capacitor had a little-bit of hump, I had a new one same spec and changed it. New one rated to 9000h.
- Did some soldering: Main AC input -> Switch (Red) -> Monitor AC output -> the new PSU PCB. This is why I needed heat shrink tubing.
- Further soldering: Removed previous factory 12V fan ("new" PSU), added fan connector so the fan can be easily replaced.
- Added a 8cm AMD factory CPU cooler (Cooler Master).
- Put everything inside the old PSU case.
- Used wood screws for the fan... don't tell anyone.
- Turned on, measured voltages. I got 10,8V instead of 12V and also got a bit sad at this point and less confident about this PSU... too late.
- First tested on a different low value Socket 7 AT board. Board running. Idle at: "No boot disk". Measured again, exactly 12.00V (and 4,99V). Confidence back!
- Important: with nothing connected the 12V measures way less that 12V! Found out that many classic power supplies require a load on the 5V or 12V rail to properly regulate and output correct voltages.
- Reassembled everything. Good airflow.
- Works and wow how much quieter it got. That original 220V fan was very noisy!

Before:

After:

JAKra85 wrote on Yesterday, 12:07:

- Turned on, measured voltages. All good. I got 10,8V instead of 12V and also got a bit sad at this point and less confident about this PSU... too late.
- Tested on a different low value AT board. Measured again, exactly 12.00V (and 4,99V).
- Important: with no load the 12V measures way less that 12V!

I would fear that the lower unloaded voltage could be a symptom of some regulator not working correctly - maybe from dried up capacitors?