You're pretty much hit the outer limits of possibility there, 800 FSB P4s are going to be the absolute fastest you can get--period--industrial or not.

That said, P4 motherboards with ISA are more prevalent that people tend to realize, case in point:

http://www.ebay.com/itm/SOYO-SY-P4I845PE-ISA- … =item27deb25826
http://www.ebay.com/itm/MSI-MS-6551-Motherboa … =item417c764327

Neither of those are 800mhz FSB, but they do exist, I've seen them up for sale before.

Now, industrial boards with ISA slots exist with much faster CPUs, modern Core i7s as a matter of fact. The problem with anything faster than a Pentium 4 (or that has an Intel chipset that was made after the ICH8xx series) is that, while ISA slots can bridged to PCI, there simply doesn't exist the logic in them to route ISA DMA to the DMA controller (meaning no sound blaster compatible digital audio)... And to be blunt, those later (and integrated) DMA controllers probably wouldn't be able to work with ISA's method of DMA anyway.

In my opinion you don't need an ISA sound card for those late SVGA games in a system like this. The reason being that PCI sound cards have no problems with games like Duke Nukem, Descent, Quake, etc etc

I have heard rumours that Commell MB-P4BWA (up to Core 2 Quad) is working with ISA soundcards; however, even if it does, it has neither FDD nor IDE connector and has a PCI-E slot for graphics.

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Advantech AIMB-742 - 2 ISA slots, Socket 478 800 Mhz FSB, up to 3.0 Ghz CPU, AGP 4x/8x.

kithylin wrote:

The second motherboard you found there, the MSI one, I found the manual after some searching and it lists the block diagram for the layout and the ISA slot is routed through "PCI-to-ISA Bridge", so likely that one is like you said, wrapped through PCI and probably wouldn't work. That soyo board looks nice, I'll watch that one.

Oh, no, it's not the bridge itself that creates the incompatibility, it's the chipset not understanding the way the bridge "tunnels" the DMA that keeps it from working. That board will work perfectly.

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bristlehog wrote:

Advantech AIMB-742 - 2 ISA slots, Socket 478 800 Mhz FSB, up to 3.0 Ghz CPU, AGP 4x/8x.

If you want the fastest possible ISA system, you'd need one of these: http://buy.advantech.eu/PCA+6120P4+0B2E/PCA+6 … 6120P4-0B2E.htm

Then I think you can plug in TWO of these: http://buy.advantech.eu/PCA+6011G2+00A1E/PCA+ … 011G2-00A1E.htm

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Yeah that was just an example to show how ridiculous industrial boards can get.

Do you really need a machine THAT fast? A 440BX with Coppermine or Tualatin is probably faster than you'd ever need, and can be found for cheap as long as you don't get it from ebay.

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Have you tested it with write combining enabled manually, or with windows in the background?
This is a Tualeron ES CPU + voodoo 3 AGP graphics, running Quake I timedemo 2 at 640x480:
4x100=400MHz does 50,9 FPS with write combing, 27,0 FPS without.
4x133=533MHz does 67,5 FPS with write combing, 35,8 FPS without.
(Write combining enabled with 'MTRRLFBE.exe LFB WC')
Write combining in combination with a fast bus is where the gold is, for DOS VESA modes.

60 FPS is a bit of a luxury, 30-40 is fine usually.

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IIRC the last Intel chipset with 8237 emulation is 865PE/875P.
Not sure about NMI support...

[quote="kithylin]That goes along with another problem, I've never in all my searches found any PCI sound cards that are 100% compatible with ms-dos games run in DOS mode (not ran through Windows 95/98).[/quote]
You may want to research "SB-Link". Those P4 boards with ISA are rare and expensive.

kithylin wrote:

I tried it on an Athlon K6-II+/600 system and it didn't even engage, came up with errors

The later AMD K6 cores have a similar write combining trick, but it is not compatible with intel MTRRs, as introduced with the Pentium Pro and Pentium II. You need a different utility for K6. 'K6OPT' or something? I have not tried this myself.

kithylin wrote:

then tried it again on a similar AthlonXP system on a Soyo Dragon Plus! motherboard, and it appeared to enable there, but showed no difference in benchmarks.

"The AMD Athlon family provides 8 Intel style MTRRs" So it should work. 320x240 is too easy for an Athlon anyways, maybe use PC-Player benchmark instead, in 640x480 or more.

Usually loading Windows enables MTRR WC too, even when you exit to DOS after loading windows.

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For K6-2CXT (and newer) I use SetK6d, if your BIOS does not support setting the MTRRs already.
For comparisons you should be also aware that in most cases the setting does only apply for the Linear Frame Buffer area. To see an effect you have to make sure that your benchmark application actually uses the LFB and not banked VGA. Enabling this for banked VGA modes is for Modes problematic that use some sort of "non-standard" framebuffer memory layout representation as ModeX. S3SpdUp is e.g. a tool that can enable this.

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