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Would you buy a DOS PCIe card?

Tiberian Fiend

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Just as a thought experiment, would you buy a PCIe card that allows you to run DOS programs without software emulation in a modern PC (sort of a system on a card)? If so, how much would you pay, and what features might it have?
 
I'd buy a PCIe card that let me add a proper floppy disk controller to a modern desktop PC. A PCIe sound card with pure DOS Sound Blaster compatiblity would be nice, as would perhaps a more DOS-compatible VGA card. At least PCI/PCIe serial and parallel cards exist. But the whole problem is that PCI/PCIe prevents full compatiblity.

Could an all-in-one card with a CPU and IO devices overcome those problems? I think you would wind up having to put all I/O devices directly on the board. And at that point, what is the point of having the rest of the PC in the first place?
 
What I want is a USB 5.25" drive :p

I'm not sure if I'd use a PCIe Emulator for games or anything, but it would be handy if it had proper hardware ports, could be useful with development (serial, parallel etc).
 
Could an all-in-one card with a CPU and IO devices overcome those problems? I think you would wind up having to put all I/O devices directly on the board. And at that point, what is the point of having the rest of the PC in the first place?
I'd think it would need an x86 CPU on board, maybe with on-board memory. Do modern CPU's even still have 16-bit instructions?

At the very least, a system on a card would remove the need for a separate case and power supply, reducing space requirements for a dedicated DOS machine.
 
The reason I run DOS is for access to old I/O devices. That means an ISA bus and the usual legacy support.

My guess is that stuffing it all on a PCIe card might be difficult.
 
The reason I run DOS is for access to old I/O devices. That means an ISA bus and the usual legacy support.

Shouldn't an ISA subsystem in-a-box be a fairly trivial thing to implement nowadays? If the popular DOS emulators could talk to the driver, that would get past the "I need it for X which is only available on ISA" (which is my main reason for DOS on real hardware).
 
I'd think it would need an x86 CPU on board, maybe with on-board memory. Do modern CPU's even still have 16-bit instructions?

At the very least, a system on a card would remove the need for a separate case and power supply, reducing space requirements for a dedicated DOS machine.

16-bit instructions are available to just about all X86 compatible processors when running in 32-bit mode but are difficult to access if the processor is in 64-bit mode. There might be an industrial or specialty model that does not permit usage of 16-bit instructions but I don't know of one. The problem with these newer CPUs is the lack of older I/O in the related chipsets. Can't boot a floppy only OS if the system can't use a floppy.

Though take a look at http://www.trentonsystems.com/single-board-computers/iob33-pcie-and-io-expansion-board Some PCIe SBC designs still advertise IDE and floppy connectors on board. Very expensive options.
 
I'd think it would need an x86 CPU on board, maybe with on-board memory. Do modern CPU's even still have 16-bit instructions?

At the very least, a system on a card would remove the need for a separate case and power supply, reducing space requirements for a dedicated DOS machine.
I've booted DOS 1.0 on an ASRock 990FX Extreme 4. See this thread: http://www.vintage-computer.com/vcf...nt-motherboard-FDC-and-quot-legacy-quot-tests

Current CPUs do still have "16-bit" compatiblity for virtualization and booting. As far as I know most current computers still offer BIOS booting, which means they can load DOS. But it is mainly for bootstrapping 32-bit Win 7/8, so compatibility is poor and decreasing.

Most of the hardware compatibility has been chipped away. The four boards in the thread above are probably the last to have a real FDC. But USB or SATA devices can usually still be used to boot DOS.
 
Shouldn't an ISA subsystem in-a-box be a fairly trivial thing to implement nowadays? If the popular DOS emulators could talk to the driver, that would get past the "I need it for X which is only available on ISA" (which is my main reason for DOS on real hardware).

Well, there is a USB-to-ISA box that's been around for awhile, but it works for a very limited number of devices. I'd much rather have an ISA-with-CPU box with perhaps a CF or SD drive as mass storage. Right now, using a "tweener" or 5 does the job.
 
I'd much rather have an ISA-with-CPU box with perhaps a CF or SD drive as mass storage. Right now, using a "tweener" or 5 does the job.

Me too. Actually a Raspberry Pi type of device would be nice. A little board with some low power Pentium chip and the usual DOS ports* would be nice for space and power saving. How about somebody make us a nice DOS Pi? I'll put on the coffee.

* Parallel, serial, ethernet, VGA, keyboard, and possibly MDA.
 
Nope, I have too many native DOS running machines to bother buying one.

DOS gamers would need floppy and game ports plus SB hardware to be useful. People who run old industrial apps would need ISA card support. Kind of hard to get that from a PCIe card.
 
...would you buy a PCIe card that allows you to run DOS programs without software emulation in a modern PC...
i probably would not buy it. I haven't owned a modern desktop in 10 years. in fact, the newest desktop i have is a 32-bit P4 dell optiplex 260. i got it free in 2004, and used it as a server lab environment for work.
i've been entirely on laptops since about 1998. -- i'm so boring.
i'm just informing you of my PC habits.. there may be others like me who don't have PCIe and may never..
 
I've been entirely on laptops since about 1998. -- i'm so boring. I'm just informing you of my PC habits.. there may be others like me who don't have PCIe and may never..

I've never found laptops very practical, but I do have multiple PCIe slots available. Still, like you I'm PCIe skeptical.

My question is how would you run DOS from there? As an embedded system? How would you be able to access it from somewhere else, such as your operating system, without some form of interface? I guess it could have an IP and hook into the OS networking somehow. In the end it seems like the only advantage would be the sharing of a power supply. That doesn't seem like a particularly useful thing to me - considering how much trouble it would be to get support written for all the different operating systems out there.
 
* Parallel, serial, ethernet, VGA, keyboard, and possibly MDA.

There are several brand new Intel Z97 based motherboards with DOS compatible parallel, serial, and PS/2 ports on them. All located not too far from the fancy new M.2 SSD slot.
 
There are several brand new Intel Z97 based motherboards with DOS compatible parallel, serial, and PS/2 ports on them. All located not too far from the fancy new M.2 SSD slot.
I'm not getting your point. I just did a (very quick) search and the only boards I found were huge and looked like they needed quite a fancy power supply similar to a regular desktop computer. From a DOS point of view that makes them exactly the same as your common P1 -4 throwaway. Are there some small ones the size of a PCIe card?
 
There are several brand new Intel Z97 based motherboards with DOS compatible parallel, serial, and PS/2 ports on them. All located not too far from the fancy new M.2 SSD slot.

Which boards are these? and have you used them to see if they are truly compatible?
 
I'm not getting your point...

I think the point was that it's still possible to buy a new PC with "legacy" ports on it, IE, you don't need some hypothetical add-in computer-on-a-stick card to get them, nor do you necessarily have to dumpster-dive for an old PC.

I'm sort of confused what need a device like this is supposed to satisfy. If it's just about running the software modern CPUs are fully backwards compatible with 16 bit x86; most of the issues you'll have trying to run an ancient OS on a new PC relate to the less-than-perfect backwards compatibility of devices like VGA cards, disk controllers, etc. (many of which really only raise their ugly heads if you're trying to run something more elaborate than plain-vanilla DOS), BIOS incompatibilities like you may have seen on a real clone back in the day, or the old software simply being "broken" by exposure to a CPU much faster than it expects. (Plenty of us saw that back in the 386 days) You can resolve most of the hardware issues by using a hypervisor/virtualizer to set up a sandbox environment; VMware/VirtualBox/KVM/etc support "faking" a decently wide range of disk controller, video, and sound hardware and can run 16/32 bit guests on 64 bit hosts with a fairly insignificant performance hit. After all, hypervisors allow most CPU instructions to execute natively; on a CPU with VT-x support basically only hardware calls need to be intercepted and emulated. For software that *is* broken by massive speed increases game-targeted emulators like DosBox are an excellent fallback position. (For something like a DOS game it has to run "fast enough", why care if there's a lot of CPU overhead from the emulator if it achieves that?)

On the flip side, if this is about having access to genuine legacy hardware obviously a PC-on-a-PCIe card is going to have problems fulfilling that need. If you want it to have a full slate of legacy connectors it's going to be a beast of a thing and not cheap (look at units like the Sun PCi IIIpro, for instance; with a whole slate of dedicated I/O it takes up three slots), and if your needs involve ISA or something then you're looking at having an expansion chassis cabled to it as well. Going by what things like a Thunderbolt PCI chassis costs, and factoring the lower volume, I'm guessing a complete PCI-e PC+ISA box would cost somewhere well north of a grand to churn out. Not sure the market exists to bear that, but in theory I suppose such a thing might have industrial customers. But at that point the obvious question becomes: "why make it a PCIe card at all, why not just make a standalone PC motherboard with low end CPU, legacy ports, and an ISA slot or two tacked on?". It would undoubtedly be cheaper and more efficient.*

If you're really desperate to read floppies on a legacy-free PC a lot of them still have a parallel PCI slot. There may not be a good solution for getting a floppy controller into PCIe but there are several options for PCI. (Including Catweasels which are perfect for disk imaging, far better than a normal floppy controller.)

*EDIT: Doh, of course you can get new motherboards with ISA slots. I should have known that. This is just one of many hits.
 
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