liqmat wrote:Cleaning up an Intel branded Pentium 100 desktop for a Youtube demo of the Cardinal SNAPplus. The Socket 370 board I picked up at Alibaba NIB had one ISA slot, but the performance of the ISA slot was insanely bad. A member at vcfed.org said it might be because late Socket 370 boards did not implement DMA for the ISA slot. Have no idea, but this should do the trick for a MS-DOS build.
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Wish I'd seen that post; the VIA chipset on your 370 board absolutely does do proper ISA DMA, as does virtually every chipset that supports the P3. It wasn't until the (late!) P4 & Core era that ISA DMA got "obsoleted." (Even SOME P4 chipsets do ISA DMA just fine, e.g. i845/865.) Boards with those chipsets run ISA through a bridge chip anyway & you're extremely unlikely to run into one unless you deliberately order it from an industrial supply.
THAT SAID... the VIA KT133 and its variants are known to have pretty abysmal DOS performance & a lot of incompatibilities anyway; they're really better suited as a Win98/NT chipset. You may well have been running into an issue with the chipset but AFAIK it's not lack of DMA.
There's also the possibility that your board has some shonky half-featured pirate chipset conveniently labelled as a VIA KT133. 😜 The Gigabyte board it's a knockoff of had the real thing.
Anyway the P100 setup should work out nicely. Looking forward to the demo vid.
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