Today I got a fully built replica A4091 Zorro 3 SCSI card delivered. The A4091 was a SCSI 2 controller for the Zorro 3 slot, it was made by Commodore. This is a reverse enginered version that you can find prebuilt on the internet or build yourself. Find out more about the original C= 4091 card here and the new replica A4091 SCSI card here.
I watched the presentation of this card on an Amiwest stream a couple of years ago so its exciting to have the real card in my hands.
Advantages of SCSI in an Amiga
The advantage of using a SCSI harddrive and a A4091 in a Zorro 3 Amiga is that it will have faster transfer speeds than IDE. SCSI is also less heavy on the system as the card has its own brain to process file transfers taking up less CPU time than IDE. This is good as Amiga is limited in CPU power (at least with a real CPU).
Zorro 3 only!
This card only works on the Zorro 3 slot. That is good news since it means better performance than a Zorro 2 card/slot. But it also means it will only work on the A4000(T) and the A3000(T). The Amiga 3000 already has SCSI on the motherboard, but if that does not work well, this card could be the solution.
Hardware setup
This card will probably end up in my A4000TX or in my A4000D. The A4000T already has SCSI2 and is basically the A4091 card implemented on the motherboard (well, the main chip is the same). As my main systems already got 060s, graphics cards and plenty of memory this is a welcome addition in squeezing out the last performance before I go into the world of PiStorms.
I will run a ZuluSCSI card on mine as I have banished mechanical harddrives from all my computers. The ZuluSCSI can emulate multiple harddrives (and CDs) stored as files on an SD card.
Purple Amiga A4091 SCSI 2 card
And I actually lied a little when I said that it was exciting to finally have the card in my hands as I already built a purple A4091 SCSI 2 card last year.
Here are some new Amiga PCBs for some new projects I got this week:
GottaGoFaZt3r memory card (will do the 256 MB version and probably a second card).
PiStorm16 x 2
Prometheus clone
MpegIt for the Prelude Amiga sound card
Prelude sound card PCB (not in the picture)
I also have two Amiga graphics cards in my todo list:
GBAPII++ graphics card
Mini GBAPII++ graphics card
And lets not forget the ReAmiga 3000 PCB I got late this week too! I have had a broken Amiga 3000D motherboard in my stash for years so finally I will be able to shake some life into it again!
So lets just say a massive BOM will be ordered soon!
Today I picked up a small parcel that was sent to me, the parcel contained a GBAPII++ mini Amiga graphics card PCB. The GBAPII++ is a half size Zorro 2 Amiga graphics card based on the Cirrus Logic GD5434 chip, you can read all about that project here. This is a smaller version of that card – It is intended to be used with the Denise A500+ clone (Mini-ITX) but can be used on all Amiga systems with Zorro slots. You can read all about the mini version of the graphics card here.
Specification of the GBAPII++ card
This is a Zorro 2 card, it has 2 MB memory and is comparable with the Picasso 2 graphics card in performance (give or take performance in some tests). It is a perfect match for Z2 and 030+ systems IMHO but is not really a competitor with the zz9000 regarding performance (in a Zorro 3 system).
Lets take a look at the GBAPII++ card
Front side of the GBAPII++ Amiga Zorro 2 graphics card
Usually I prefer to build projects from scratch but in this case I did not mind a version where the passives where already pre-installed. The GBAPII++ mini version uses mostly 0603 component sizes. That is 1.6 x 0.8 mm in size, not impossible to solder, and to be honest not that challenging, just very tedious. Especially if you do not have a proper workshop with microscope.
Here is the back of the graphics card, not much happening just some 0603 parts
The missing components are 2 MB memory consisting of four chips, SOJ40 (this is the same memory type that is installed in an Amiga 1200 rev 1.4d). The card needs one CPLD, two ICs, crystal and the GD5434 chip. The Cirrus Logic chip can be taken from a PC graphics card. Occasionally NOS chips show up on Ebay from time to time. Expect to pay 25-40 euro for the graphics chip alone (and more for the full graphics card).
I also got this little VGA out PCB that hooks up to the graphics card and fits neatly at the back of the Denise Amiga 500+ clone.
I built my second Amiga 2000 EATX last year, it is a beautiful clone of the Amiga 2000 remade into a standard extended ATX format so it can fit a standard EATX case. You can be sure that I will add an article about that motherboard here in the future. The author of that project has also made the n2630 project, its a clone/reimplementation of Commodores 030 card for the A2000, the Commodore A2630.
To be honest, I wish there was a modern 060 or 040 card we could build for the A2000 since I think 030 is just too slow these days – at least for my modern Amiga standards. To be fair while the A2630 was 25 Mhz this one runs at 50 Mhz, so its a little bit faster. 040 runs so hot, but would be a perfect fit for the A2000EATX because of the improved case airflow (and having an 040 in one of my machines could be interesting to compare performance with 060 machines).
Anyways, I should be glad with what I have and I am thankful that we can build this cool modern 030 card for our A2000 computers. And the n2630 is such a nice compliment to the A2000 EATX motherboard having IDE/CF slot built in.
Building the n2630 for my A2000EATX
I decided to build my n2630 card earlier this year with 128 MB fast memory. There was an option to go for 256 MB fast memory also but thought it was not really worth it, maybe I will regret it in the future. Otherwise this build was very straight forward. It uses three CPLDs and six memory chips.
There was some parts that was difficult to find, first it was the 030 CPU socket. I actually got the parts number for one that was availble on Mouser after asking around, surprised about that. The CF slot at the back of the card needs to be the right one to fit solder points on the board, ask on the Discord if you wondering what type you should get if you are building one. Other than that it was an easy build. There are also two eproms you need to have and program, but as usual, most stuff that is rare can be found with some patience.
I have since mounted an FPU to the card and I also got a 3D printed bracket so I could secure it in my regular ATX tower that was converted to EATX. I ran out of black pin stripes that is why I used yellow and green (it was also a joke about obsessing over the color syncing of hardware).
I finally got the last part that was missing from the BOM from a seller in Germany so that I could finish my Amiga 4000T motherboard replica build.
The motherboard is fully built, so is the AV module, the disk module and the ATX I/O module.
Unfortunately I do not have any AT PSUs anymore. I have ordered an AT to ATX converter, hopefully I can test the board once it arrives next week.
Looking back at building the Amiga 4000T
I think this build was fairly easy. The most difficult thing was locating parts on the PCB, thankfully there is an Ibom for both the main board and the modules here. If there was no Ibom, I honestly dont know how I would placed some of the components as placement can differ from Commodore made PCBs. You can not just compare part placement on pictures.
I will go through the build in more detail when I have tested the board fully.
I am happy to say that my A4000T build is soon finished. I am waiting for some pinstrips and a couple of passives I missed out on in my first order of components. When I get them I will proceed with the video and Zorro slots and also the three ISA slots (and the P8P9 power connector).
I am always nervous when soldering the 200 pin KEL CPU card connector. If you do it wrong side, you have to desolder it and turn it around – that is a lot of work. Better option is to triple check everything before soldering.
The backside of the A4000T PCB contains a lot of passives to solder on. All passives are 1206 though installation went fairly smoothly.
All thats left to do is to solder in the pin strips, 72-pin SIMM sockets, P8P9 socket, edge card slots and some small parts and then I will clean up the bord, inspect everything twice and do a test run with Diagrom. You can be sure I will post about it here!
I am building an Amiga 4000T motherboard and its modules at the moment. Here is the disk module for the A4000T. It is almost fully built, missing two double row pin headers and screws for the external SCSI2 port.
The disk module has the internal 50 pin SCSI port and the external SCSI2 port. It also has the SCSI switches (accessible from backside) and floppy port. It is attached to the Amiga 4000T motherboard on a pin header.
Work continues on my Amiga 4000T replica build. On the A4000T a lot of functionality is placed on daughter cards such as audio and video out that is placed on the AV module. The A4000T AV module slots into the Amiga 4000T motherboard in a 40 pin 20 x 2 double row 2.54 mm pin header.
As you can see on the image above, the AV module is about 95% done. It is missing the headphone jack, 20 x 2 double row female connector and two 3904 transistors (and some jumpers).
The BFG9060 is a modern 060 turbo card for big box Amigas. It can take either a 040 or 060 and has 128MB RAM. It is occasionally available as a fully built card either with or without an 060 or you can order a PCB and build a card yourself. Read more about it and who made it here.
I decided to build my two BFG9060 cards myself as I enjoy building hardware and they would compliment my A4000 systems well (that I also built as kits). I have also read a lot about the BFG project and like it! On this page I write about the first card I built and that I tried to overclock to 100MHz.
Building the BFG9060
The card is under construction
The most difficult parts to find for the BFG9060 IMHO is the CPU (I thought), the CPU socket and the edge slot (KEL connector). 060 CPUs do not grow on trees, however I still think that they are surprisingly easy to find on the second hand market (in both crippled non FPU versions and full version) and all things considered they can still be had for a reasonable price. The 060 can actually still be found for a relatively ”good” price, between 2-300 euro.
The 68060 CPU socket is difficult to find but not impossible, I got one from a friend in the hobby (as well as the KEL connector) but decided not to use it in this build. I decided to solder the 060s directly to the BFG, more on that later. The KEL connector is difficult to find but there are some builders of these cards that might have a spare one to sell. Keep in mind that the CPLDs are EOL and will be difficult to find in the future (for a good price). Other than that its mostly a straight forward build.
Rev. 6 68060 CPU
Apollo 1240 upgraded to an 060 card
I have an old Apollo 1260 that I got for a great price back in 2008. I have been running it in my old A1200 at 50MHz and it has been great during those years, I love an 060 in an Amiga, makes the whole system much more fun to use.
The Apollo card had a rev. 6 68060 on it which the seller claimed could easely do 75MHz when he sold it to me. I never tried overclocking on the Apollo turbo card but thought that some day I would, that never happened though. Since the BFG9060 supported a 100 MHz overclock I thought it was an excellent idea trying the CPU on that card instead and finally find out how much I could push the chip.
Backside of the Apollo 1260
I sent the Apollo card to a guy who could professionally desolder the 060 CPU, it was soldered directly to the Apollo card. My hobby grade desolder station could not handle the job.
Instead of putting it on a socket on the BFG card I decided to solder it directly to the card once I got it back. It would have taken a lot of time to clean and straighten the legs out to get it to fit a socket if it was possible at all.
Overclocking the BFG9060
Revision 6 68060 71E41J, capable of 100+MHz (hopefully)
So after the card was built it was time to program the CPLDs and test the card in an Amiga. While it worked fine at 50MHz I was sure I wanted to try to get it running at 100MHz.
The later revision of the 68060 (71E41J) is famous for being able to be overclocked and running happily at 100MHz or more, the BFG only supports up to 100MHz though, but a 50% overclock was fine for me!
BFG9060 testing session with temporary heatsink (an old official 040 heatsink)
It is here I found a problem. The card refused to start when jumpered to 100MHz. I could feel the CPU getting warm but my A4000TX never booted to Workbench. However, I could get into the early startup menu with the BFG at 100MHz – That was promising!
Turned out I had to overvolt the card slightly by replacing a resistor that increased the voltage for the CPU. Keep in mind this was still in line within the specifications of the 68060 even when overvolting the card. After I replaced the resistor R9 with a 2.87K resistor, bumping voltage up from 3.3V to 3.4V, the BFG9060 happily booted at 100MHz and ran stable playing Quake demo for hours!
So on the BFG9060 the resistor R9 controls the output of the voltage regulator, acording to the info I got the corresponding resistance of the resistor on the left side below would correlate to the voltage on the right side below:
3.16K = 3.3V (default)
2.87K = 3.4V
2.55K = 3.5V
2.32K = 3.6V
I was initially worried I would be running the card hot when it was overclocked, but that proved to be false. I dont have any data, but the turbo card and the CPU did not feel hot at all. But to keep the card safe I added a tall heatsink (Enzotech) with a 2 cm tall Noctua 40 mm fan keeping the CPU cool. I have forgotten the exact part number for this cooler but it fits the 060 as a glove and clips on the CPU. The two CPLDs got black heatsinks attached with thermal conductive tape (after I took the pictures below). I am running this card in my A4000TX that is installed in a tower, it has a 120 mm Noctua fan blowing in from the front. The whole system runs cool!
Conclusion
Trucking on in 100MHz!!!
My overclocked card has been stable for more than a year (as has the Amiga it is running in). My A4000TX is a dream to use at 100MHz together with a zz9000 graphics card. Do you notice the speed increase? Yes, I feel that Workbench is more responsive and off course classic 3D games such as AmigaQuake runs faster at 100MHz. I have not had a single crash that could be attributed to the CPU card (in either overclocked or non overclocked state) which proves (for me) that the BFG in my A4000 is a very stable and dependable CPU card. Great job everyone involved in making this card and who decided to release it open for anyone to build!
