BFG9060 black screen on my Amiga 4000D motherboards, how to fix?

Here is my test setup: Acill A4000D motherboard with ReA3630 and two BFG9060 cards including Firestorm PCI daughterboard, Multifix-AGA and a replica A4000D case

I had two summer projects this year that I recently finished. One was an Acill A4000D replica motherboard and the other was a Hese made A4000+ Alice A4000D CR motherboard replica. You could say two brothas from different mothas or something…

Both motherboards worked fine when doing basic test runs, however they both failed to run with a BFG9060. All I got when running them with a BFG9060 060 CPU card was a black screen.

amiga-4000d-motherboard
Amiga 4000D motherboard in shiny red

Anyway, as usual building them up was pure pleasure from start to finish. I even enjoyed desoldering the Acill A4000D motherboard from a few passives and pin headers someone else had a false start with. I mean, off course you want a full set of pin headers soldered to your 400+ small parts PCB (not really).

The A4000D motherboard fully built with a BFG9060

The motherboard was all built up and looking good in shiny red matching a BFG9060 with a mystery (rev. 1) 060 I built last year.

As good as it was looking it failed to run with the BFG9060. It was working fine with the A3630 CPU board I built earlier this year, but not with the 060 card. That reminded me that I had the same problem with my Alice A4000D motherboard a couple of weeks ago.

A4000+ Alice motherboard during assembly phase

The Alice A4000D has an 030 CPU on the motherboard so it does not need a CPU card. It was working fine with the on board 030.

Here is the A4000+ Alice motherboard during the testing phase inside the A4000D case

I got the suggestion to try a new delay line as that could be the problem the CPU card failed to run. As the A3630 has exactly the same CPU as the one mounted on the motherboard, it is difficult to say if the A3630 was running or not.

Testing the A4000D motherboard + BFG9060 with a PicoPSU

If you are in this hobby you have to grow a passion for trying all hardware combinations to find the solution. In this case, the reason for the Amiga 4000 getting a black screen when running a BFG9060 was the PSU as everything seemed to run fine with another PSU than the SFX one I had in the A4000D case.

I changed the SFX PSU that previously was working fine with the EXACT hardware setup I am running here (but different Amiga 4000 motherboard) with a small ITX PSU and suddenly DiagROM worked fine and detected the 060 CPU.

This lead me to believe that maybe the PSU was not pushed too hard as some ATX PSUs fail to run if there is a tiny load on them (or something like that). So I decided to do a final test by adding some cards to my A4000D and try the SFX PSU again.

Unfortunately it did not start with the SFX PSU and 060 card even if I loaded the machine with all Zorro slots filled, including adding an old 3.5″ harddrive.

So next step is to get a new SFX PSU. But at least I know I have to working motherboards!

3D printed Amiga 4000D front panel

I bought a replica Amiga 4000D case earlier this year on Amibay. It is really good clone of the A4000D case with the exception it has slightly better cooling, space for a 40 mm fan, was painted black, has some options the original Commodore A4000D did not have, uses an SFX ATX PSU and did not come with a front panel.

I really like the look of the A4000D (even if it is just a lousy PC case that was adapted to the A4000D in the last minute), especially the front panel. If there is a template for a professional early 90ies computer case, I think this could be one of them (together with SGI, Sparcstation and so on) – There is just something about the angled look of it and the Amiga logo inprinted in the case cover mold.

Functionality wise, the case is a disaster. The Amiga 4000D case has lousy cooling. The whole case depends on the fan in the PSU to cool the whole system. There is no active cooling at all on the Zorro board section. It has the mouse and joystick port awkwardly mounted on the side making it difficult to remove the cover. And while it has a 5.25 slot, it is too shallow and wont take a full length CD-rom (or DVD). Many of these problems has been solved in the replica case and many of these problems are not problems anymore (I never want to touch optical media again).

What about the A4000D 3D printed front panel?

Its a bit dusty in the picture but the finish is really smooth

The files for the 3D printed A4000D cover can be found here. You can find the different 5.25 and 3.5 cover slots there too. I got them printed at JLCPCB in nylon resin and something, I have forgotten, I also got the power button on a stick 3D printed. All in all the total cost was somewhere around 50 euro, very affordable IMHO. The front was printed in one piece. It has a bit of a rough look to it if you look close, but it is surprisingly well done. I do like the rough look as it resonates with the home built A4000D motherboard, its not perfect as in a factory made case/computer as it is DIY built.

However, the front panel do not fit on the A4000D case that good. The clips are too long and they are really soft and became slack quick, meaning the front panel hangs off the front of the case and just looks cheap.

How I got the Amiga 4000D 3D printed front panel attached to the case

I had an idea to use strong neodymium magnets to hold the front cover onto the A4000D case.

In the picture above you can see four round magnets and two banana shaped magnets. The banana shaped magnets came from an old 3.5″ harddrive that I recycled. These magnets are really strong.

The round magnets are also neodymium magnets but less strong. If I was to start over I would just use three of the really strong banana shaped magnets they hold the 3D printed front panel to the case strong and secure. See the peg in the bottom left corner and how it has sagged.

It looks a bit sloppy because it is, I will paint the stand offs for the magnets black and maybe even add some black bondo to them to make it look nicer. However as a proof of concept everything works and is secure. The stand offs are regular plastic pencils that I cut to lenght and then super glued to the 3D printed A4000D front, I then super glued the magnet to them and let everything dry over the night.

I thought that the magnets would work themself loose from being super glued to the stand offs but I have been proven wrong. They are secured to the stand offs and case and wont move or brake off.

Here is the case with the cover added to it, being held to the case just by the magnets. Taking it off the case needs a lot of force. To make it easier I sanded off the hooks on the pegs of the front cover to make it easier to slide out the holes of the front of the case. Again, looks rough but works fine.

Here is a closeup of the 3D printed A4000D front cover, the badge was bought from a store online.

All in all I am very happy with my black A4000D case. I think it fits into a modern office much better when it is black as so few computers come in beige these days.

Amiga 4000D maintenance

I have an Amiga 4000D that is in a work in progress state. I am in no rush to get it finished and I enjoy the process of setting it up. It is an Acill A4000D motherboard that built last year. It has a Firebird PCI daughter card, a MicroniK scandoubler and a C= 030 CPU card. Everything is mounted in a replica black A4000D case with a 3D printed A4000D front (incl. covers). Final state of this Amiga 4000 will probably look a lot different but for testing purposes, this will be fine.

Adding a IDE-CF interface to the Amiga 4000D

Today I added a slot bracket mounted Compact Flash card adapter to it so I could test out a couple of 72-pin SIMM slots. I do not have a floppy drive in most of my Amigas so I had to run Workbench of off a CF card to be able to see total memory. Thankfully I still have old school 40 pin IDE cables in my parts stash.

I used the Workbench installation from my Denise ITX Amiga 500+ clone by simply borrowing the CF card from it. I will post some more info on this beautiful little Amiga computer later sometimes.

With the CF card inserted in the Compact flash adapter my A4000D booted happily of off the WB 3.1 installation on the CF card. Having the CF card accessible from the outside of the Amiga is a must. I often find myself mounting the CF card in WinUAE to take backups and to install and transfer software.

Testing 72 pin SIMM memory

The first thing I wanted to do was to remove the 32 MB SIMM I was using in the Chip memory socket and replace it with a genuine 2 MB SIMM. All fine, the 2 MB 72 pin SIMM worked fine as chip mem! 2 MB 72 pin SIMM memory is getting more difficult to find these days unfortunately – hopefully there will be more DIY options in the future.

The A4000D supports up to 16 MB fast memory on the motherboard, either through four 4 MB memory modules or through two 8 MB memory modules. You can see that I built the A4000D motherboard with only two 72 pin sockets for fast memory, so I need two 8 MB modules to get 16 MB.

Unfortunately, I did not have any 8 MB SIMM memory (all I had was 16 and 32 MB modules) so the maximum memory I could add was 4 MB (one 16 MB SIMM becomes 2 MB in the socket). 72 pin memory modules rarely indicated memory size so it was necessary to test them in a computer. Now this is not really a problem since I will be running either a BFG9060 or a TF 060 card in this computer. But it is always nice to max out memory if it is possible to so.

Conclusion

  • I added a new thing to my todo list, find some 8 MB SIMMs.
  • I also flagged some things on the todo list as finished, CF card adapter + chip mem is working.