Something like those FPGA-Amiga solutions? Use FPGA were no chip is avaliable anymore?

Yes. They will be extremely expensive. Just look at Vampire-V2 boards, and think of the V4, wich will be build as a standalone board, when the regulair V4 have been out for some time. Just remember that the V2 has a pricetag of over 300 british pounds. So yeah... Newly produced 486/SS7 boards will be extremely expensive.

Indeed the cost would be high. Would one steal a design, design the whole thing from scratch or partner with one of the old manufacturers to do this? I doubt any less than $500 would get it done (fabrication)?

The biggest questions are... If this can be set in motion. Then... How many will be sold and how big a batch shall be made?
One way to deal with this, is to make empty PCB's, then eighter sell with or without parts, as a DIY kit.
Or make a tiny batch of 25 boards, and sell without any profit at all, just to keep prices low.

forget it

one hour of designing pcb costs at least $60, to make mobo, even such as 486 it will take several hundreds of hours.

anthony wrote:

forget it

one hour of designing pcb costs at least $60, to make mobo, even such as 486 it will take several hundreds of hours.

We have people on vogons who can and did design PCBs. There's a thread on the Video section with one member posting designs for a voodoo 3 on a dual layer PCB for example - and then there's the ARGUS project in the Sound section of Marvin. Sure, a motherboard would be a lot harder to make.

Personally, I'd pay up to 200$ for the following:

- Socket 3 486 motherboard
- ATX Form factor
- UMC or SiS chipset - maybe even a SoC like the ZFx86, with the option of disabling the CPU part and using a socketed chip.
- SD-RAM slots for memory, maybe even some fast on-board ram - 32MB is enough.
- Fast L2 cache packaged like the pipeline burst cache on socket 7 boards
- Plenty of PCI and ISA slots
- On board ATA133 IDE controller
- PS/2 for mouse and keyboard
- FSB from 20 to 66MHz, with proper dividers for 33MHz PCI operation
- CPU voltage support for 3.3v, 3.45v, 3.7v, 4v and of course 5v
- BIOS support for large drives
- turbo switch that forces the board to run @ AT bus speed (optional, but would be cool)

I guess the simplest solution would be to make something like this:

But in ATX form factor since AT cases are scarce in some parts of the world, and more PCI slots. The above board uses a ZFx86 SoC based on the Cyrix 586 core (I think - not 100% sure). The only issues with the above board is that it doesn't come with any L2 cache, and there's no way to add any - and it only has one PCI slot.

The cool part about the ZFx86 SOC is it's built on a modern manufacturing process, so it should be able to go faster then 133MHz. It supports 2x(4x) and 3x multipliers internally, and runs over the 33MHz FSB. I don't see why it wouldn't run at 2x66MHz, or 3x 66MHz for that matter. It would make for a really fun, fast 486 class machine to play pentium games on - think cyrix media GX with L2 cache and Fast FPU = ON.

A custom board would be the absolute proof that "love" knows no bounds.

I guess a price of up to 1000$ per board could be adequate as the retro-collector is usually an animal of passion. Practicability(snarky spouses aside) and reason would of course cap the price to about 200-450$ though.
The real value of having the option to buy a new "old" board which is an optimized amalgamation of minimally updated standards, must-have options and other improvements way surpasses any value being measurable in real dollars.

I think a modular approach regarding size and functionality for a select range of customers may be a long term investment.
I would love to have a base board with integrated sound(SB/Midi), video(Riva128 like + 2MB), cache(256KB), cpu(100mhz), main memory(32MB) and of course Floppy + IDE + PS/2 BUT, the board still being expandable on all fronts with PCI/ISA connectivity a given.
On top of that, next to presets, an option for fine-tuned component voltages controlled by a trimmer or bios regulated.

For industrial purpose or the minimalist the board is small(or bare/empty), functional out of the box, minimally up-gradable and "low power" while for the bleeding edge enthusiast, with the deep pockets, the board may feature the highest quality/most luxurious base configuration plus plenty of sockets(cpu, main-, cache-, wavetable-, video-memory) + extended bios, since fiddling around with hardware seems to be a good 50% of the fun.

Voila - the "Frankenstein486". 😲

Did anybody buy and test the board you posted kanecvr?

a board with vortex86-dx SoC.. (its a 1ghz 486dx), all perhiperals integrated. driop into isa backplane! that would be cool.

Xi 8088 by Segey Kiselev

Let alone a 486 logic board... You can see there how this task is costly and difficult even for "just" an 8088 XT board, not only assemble it, but also getting it to work stable. And isn't even a motherboard, but a "Processor Card" which needs an extra non shipped ISA back plane for additional bus/slot expansion.

Now imagine the complexity of designing and producing a full fledged ATX board for an in-order-of-magnitude faster processor as the 486 is, with PCI slots (modern buses are difficult to route, that's why you don't see el-cheapo ARM boards with PCI slots). I don't think you can get any price lowering than $1000 USD each piece, for a small batch of boards... And that only if you use a 486 SoC, without any external processor/coprocessor support.

BloodyCactus wrote:

a board with vortex86-dx SoC.. (its a 1ghz 486dx), all perhiperals integrated. driop into isa backplane! that would be cool.

Not everyone has access to ISA backplane boards... I for one never came across one. I do like the 1GHz 486 tough. It would be cool if we could set the speed via bios or dip switches.

Imagine a machine that can play anything from XT games (by forcing the CPU to run @ AT bus speed like on some socket 7 motherboards) up to Pentium era games - witch you can buy new. That would be awesome.

amadeus777999 wrote:

I would love to have a base board with integrated sound(SB/Midi), video(Riva128 like + 2MB), cache(256KB), cpu(100mhz), main memory(32MB) and of course Floppy + IDE + PS/2 BUT, the board still being expandable on all fronts with PCI/ISA connectivity a given.

I'd want an S3 Trio64 or Cirrus CL-GD544x on board chip, although the Riva 128 is a good dos chip as well. I'd want 8MB for the Riva tough.

amadeus777999 wrote:

On top of that, next to presets, an option for fine-tuned component voltages controlled by a trimmer or bios regulated.

That would be kickass.

hyoenmadan wrote:

Xi 8088 by Segey Kiselev

Let alone a 486 logic board... You can see there how this task is costly and difficult even for "just" an 8088 XT board, not only assemble it, but also getting it to work stable. And isn't even a motherboard, but a "Processor Card" which needs an extra non shipped ISA back plane for additional bus/slot expansion.

Now imagine the complexity of designing and producing a full fledged ATX board for an in-order-of-magnitude faster processor as the 486 is, with PCI slots (modern buses are difficult to route, that's why you don't see el-cheapo ARM boards with PCI slots). I don't think you can get any price lowering than $1000 USD each piece, for a small batch of boards... And that only if you use a 486 SoC, without any external processor/coprocessor support.

Nobody said it would be easy... but it is possible, and it could make money if crowdfunded trough something like kickstarter while being sold in parallel on it's own website.

To keep cost down, unassembled kits could be sold. Just provide the PCB (with BGA parts pre-soldered) + the rest of the parts as a kit, just like this: http://www.mtmscientific.com/pc-retro.html

I know I'd personally want the unassembled kit, and it would be great fun to put it together myself. Like I mentioned before, BGA parts would need to come pre-soldered, since they require specialized equipment to solder correctly. PGA parts can be soldered by the buyer by means of a SMD rework station witch is not an expensive tool.

I'm going to order one of those boards with 512k of ram. Total cost is 200$, and you get a DIY IBM XT clone - awesome.

Of course there should be an option for pre-assembled boards, for those who lack the skill and equipment, or are simply not interested in that aspect.

Kits are an awesome venue - just like in the ZX8x days, with the exception that the thing you're building is much more sophisticated.
Really cool!

this particular xt board is 2 layer, they are very cheap, it like slighty expanded zx-spectrum board. for 486 chipsets you'll never find datasheets ( i presume). for super s7 chipsets boards there must be at least 4 layer pcbs until certain impedance required. if so, there must be 6 layes pcb.

most of you don't realize how much complicated task it is to produce even 25-year old harware replica

Hey if we raise about a million we can probably get a chipset done on 32nm asic... 🤣

But stuff like this exists, check comments for more.. https://hackaday.com/2017/11/03/386-too-much- … 186-in-an-fpga/

Just fyi, modern high end atx boards can cost upto 100k to get into production.
Lower end ones are around 50k.
Now a 486 board is nowhere as complex as a modern baord, but find a supplyer for the parts and engineeris that know how to develop 486 class hardware theses days.

I can see why some folks would like this, however:

1. Are late model 486s that scarce? I haven't checked Ebay for 486 prices lately.

2. Is there an off-patent, cheap and/or open source 486 core or SOC to use for the cpu? It seems like either Intel or AMD would still have these locked down, even though they can't be making them much money these days, maybe not even in embedded systems.

Even if point 2 is not a concern, and 486s are still common enough on Ebay, it might be cool to do from a "design a new board with everything you could possibly want, that runs up to 300mhz (or whatever arbitrary speed) and can clock down to 4.8 or 8mhz if necessary.

But then you still need to get someone to design the dang thing, and you need to make enough of them that they would only cost in the range of $200-$450, as others have pointed out. I think to get prices that low you would probably be talking orders of 1000 parts or more. Anyone here done serious board manufacturing at the hobby level that cares to comment?

Jade Falcon wrote:

Now a 486 board is nowhere as complex as a modern baord, but find a supplyer for the parts and engineeris that know how to develop 486 class hardware theses days.

Well in '91 33mhz digital signalling was a bit bleeding edge, any CAD layout programs were probably on grunty minicomputers, and still had to be hand optimised by engineers who really knew their shit. ... but... since then all that knowledge and experience has got distilled into the PCB design tools that are around now and run on desktops, those cheap and common tools are maybe 5 years behind bleeding edge now, but as long as you want to do stuff up to that level, should be great. I mean look at that kit up there, slapping that together in 1979 would probably have been good for a Master's thesis in E-E, now hobbyists do it.

Well, while we're at it, add into the design a SATA controller from the FSB that acts as a separate RAID controller - since finding GOOD working PATA hard drives is getting hard to find. The controller could be SATA 1.5Gbps revision (SATA 1 speeds) and could completely ignore size limitations. The only limitation on a board like that would be OS format limitations (say, Windows 98 using FAT32). You could have built-in Sound Blaster 16 too, using the ISA bus so as to be fully compatible with DOS and Windows.

XT class hardware is nowhere as complex as a 486 system. If this was not the case we would see 486 class system kits.

Yeah they cheated and only brought 8 bits of bus out. Slackers.

You really dont know what it takes to develop hardware. Go ahead and develop a 486 motherboard. Or find someone that can