VOGONS


First post, by captain_koloth

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Hello all:

I want to build the most powerful DOS PC I can that has support for ISA slots (Sound Blaster AWE64 forever!). Based on my research I think this would bring me to a P3 Tualatin or AMD Socket A Thunderbird board, but I am having trouble finding an affordable one. Can anyone recommend me a motherboard in one of those categories that, in decreasing order of importance:

1) Has at least 1 ISA slot (more is better!)
2) Won't cost me an arm and a leg... maybe just an arm
3) Supports 5.25" floppy controllers
4) Has an AGP slot

Recommendations?

Reply 1 of 11, by megatron-uk

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If you want the most powerful DOS PC with working ISA slots, then you're looking at much, much later than P3 or Athlon. They are available for late P4 (LGA775) as well as for select Core and i-series processors.... but, they come at a price; from P4 upwards they were aimed at the embedded and industrial control sectors, so they tend to (a) be not very common, and (b) be more expensive than the typical desktop equivalent.

You do have to be careful, as the functionality of ISA DMA varies depending on the chipset implementation (this page explains it fairly well: https://flaterco.com/kb/ISA_chipsets.html), but they are out there.

Here's a link that shows just how late some designs came with ISA slots:
http://www.ibt.ca/v2/industrialboard/lsm.html

I got myself one of these (i845G, with AGP) a good few years ago and can verify that ISA DMA works perfectly:
http://www.ibt.ca/v2/items/mb800/index.html

Late designs with ISA slots are pretty easy to find, but those with DMA support (since you're building a DOS PC you likely want ISA soundcard support, which implies DMA) are, like I say, not so easy to find though.

My collection database and technical wiki:
https://www.target-earth.net

Reply 3 of 11, by Oetker

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An Intel chipset board that natively supports Tualatin will be 815 chipset based and that means ISA slots behind a bridge, which means the same issues as with the socket 775 boards. Native ISA means 440BX, which means not all boards can take 133mhz and I'm not sure if there are 440BX boards that can take Tualatin chips without an adapter (if you don't have the chip yet you could order one that includes an adapter). There's Via chipset boards that do it all, I think.

Fastest Tualatin Chipset / Best Pentium III Motherboard

Reply 5 of 11, by dionb

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There was an Abit KT7A for a nice price on Amibay yesterday. Too late now but it would have been a perfect match. Something similar could still fit the bill, so I wholeheartedly second the GA-7IXE4 suggestion.

Reply 6 of 11, by drosse1meyer

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Oetker wrote on 2021-03-11, 21:14:

An Intel chipset board that natively supports Tualatin will be 815 chipset based and that means ISA slots behind a bridge, which means the same issues as with the socket 775 boards. Native ISA means 440BX, which means not all boards can take 133mhz and I'm not sure if there are 440BX boards that can take Tualatin chips without an adapter (if you don't have the chip yet you could order one that includes an adapter). There's Via chipset boards that do it all, I think.

Fastest Tualatin Chipset / Best Pentium III Motherboard

Yea I was gonna say something w/ 440bx is probably the best bet for a 'fastest' DOS machine that still retains ISA support, though some games won't run properly at the higher clock cycles of a p2 or p3

P1: Packard Bell - 233 MMX, Voodoo1, 64 MB, ALS100+
P2-V2: Dell Dimension - 400 Mhz, Voodoo2, 256 MB
P!!! Custom: 1 Ghz, GeForce2 Pro/64MB, 384 MB

Reply 7 of 11, by Joseph_Joestar

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You can even run an AthlonXP in certain SocketA motherboards which have ISA slots, like the KT7A. Depending on the board revision and BIOS version, it may be detected as an "Unknown Processor" but it will work just fine. Have a look at my AthlonXP build for example.

As an added bonus, some of the earlier AthlonXP models like mine have their multiplier unlocked, so you can downclock them to 500 MHz (5x100) if you need to slow things down. Using Throttle and SetMul allows for even more slowdown options.

PC#1: Pentium MMX 166 / Soyo SY-5BT / S3 Trio64V+ / Voodoo1 / YMF719 / AWE64 Gold / SC-155
PC#2: AthlonXP 2100+ / ECS K7VTA3 / Voodoo3 / Audigy2 / Vortex2
PC#3: Athlon64 3400+ / Asus K8V-MX / 5900XT / Audigy2
PC#4: i5-3570K / MSI Z77A-G43 / GTX 970 / X-Fi

Reply 9 of 11, by Warlord

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What you are looking for is a computer that is strong enough to run the most demanding DOS games, late 90s dos games at high res and FPS. And can down clock enough to run older dos games that don't like a powerful dos system.

You don't want a computer that can run windows 10 or XP its a waste of time. Trust me.

Try a VIA C3 setup . I think C3s can still be had for pretty cheap, There are lots of unloved socket 370 VIA chip set boards out there with appropriate VRMs of 1.4v compatible with c3s. Get 128 MBs of ram. Find a AGP card with good dos compatibility.

Or go the socket 7 K62+ 3+ rout this is more expensive probably than a c3 setup and doesn't down clock as good.

Reply 10 of 11, by BetaC

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LightStruk wrote on 2021-03-12, 02:32:
captain_koloth wrote on 2021-03-11, 20:17:

1) Has at least 1 ISA slot (more is better!)

What would you use a second ISA slot for? Seriously.

Having two sound cards to circumvent known issues with certain ones is a reason.

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Reply 11 of 11, by gaffa2002

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Well, last year I built a “Mega DOS” PC similar to what you have in mind.
The motherboard I use is an EP-7KXA, which is for Slot A CPUs, has one ISA and one AGP slot. After getting around some issues like the 40Gb hard drive causing general protection fault errors in Windows 98 (solved by limiting its size to 32Gb through its jumpers) and instability running 3d accelerated games (reducing RAM from 512 to 256 solved it, maybe patching windows 98 could also work but I didn’t bother), it turned out to be a wonderful all-around DOS machine.
With it I use an Athlon 750mhz CPU, a Geforce 4 MX440 64mb AGP and an ISA Sound Blaster AWE64. All my DOS games work great as the CPU speed can be controlled using THROTTLE (the chipset allows 16 levels of throttling through hardware) and caches can be disabled using SETMUL, which gives me speeds around the 386 DX40. Newer DOS games like Blood, Shadow Warrior, Tomb Raider and Screamer 2 run very smoothly in 640x480 resolution.

Some speed sensitive games I play with it:

-Alone in the Dark (caches disabled, otherwise impossible to get the character to run)
-Alone in the dark 2 (using throttle as disabling cache will be too slow, game runs smooth, with music and the character can run)
-XCOM & XCOM 2(using throttle as it runs too fast in full speed but too slow with caches disabled)
-Warcraft (using throttle to have better scrolling speed)
-Theme Park (using throttle or game runs too fast)
-Ultima 8 (has problems with too much RAM, can be solved by creating a RAM drive to fill some of the RAM)
-Blackthorne (using throttle as there is no music if CPU is too fast)
-Alien Breed (caches disabled for sound and also needs the RAM drive workaround as the copy protection screen gets stuck with more than 32 megs of RAM)
-Descent (using throttle OR running in it in 640x480, the latter one being what I use)

Hope this information helps.

LO-RES, HI-FUN

My DOS/ Win98 PC specs

EP-7KXA Motherboard
Athlon Thunderbird 750mhz
256Mb PC100 RAM
Geforce 4 MX440 64MB AGP (128 bit)
Sound Blaster AWE 64 CT4500 (ISA)
32GB HDD