I've just noticed that the onboard IDE controller of ATC-1415 has poor speed:
https://i.imgur.com/1VtXEok.jpg
After plugging the VT6421A PCI IDE card:
https://i.imgur.com/y7ZjUsp.jpg
The BIOS version is 3.30 running Win98SE with 32MB of FPM RAM + AMD 5x86 😕
Most likely because the on-board IDE is connected to the ISA bus.
Are you sure? If I remember, the IDE of SiS 486 was quite fast. I thought ISA bus speed should be about 8-16MB/s 😕
I found this too:
Have you enabled DMA mode in Windows 95 ? (you need OSR2+ to do that)
Also, I think the chipset can have a driver to improve speed a little bit, but I'm not sure it's compatible with 95 (only DOS and Windows 3.1).
But UMC's IDE implementation isn't as good as SiS' implementation on their late PCI 486 chipset.
SiS supports PIO4, UMC supports PIO3 at best. (And no it's not connected to the ISA bus as far as I know, thankfully)
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wrote:I thought ISA bus speed should be about 8-16MB/s 😕
ISA is theoretically able to transfer 16.6 MB/s at most, but that's just a figure. IDE over ISA never reached speed even close to that.
wrote:
PCI-to-ISA-Bridge with IDE. That's quite unambiguous to me.
wrote:Have you enabled DMA mode in Windows 95 ? (you need OSR2+ to do that) […]
Have you enabled DMA mode in Windows 95 ? (you need OSR2+ to do that)
Also, I think the chipset can have a driver to improve speed a little bit, but I'm not sure it's compatible with 95 (only DOS and Windows 3.1).
But UMC's IDE implementation isn't as good as SiS' implementation on their late PCI 486 chipset.
SiS supports PIO4, UMC supports PIO3 at best. (And no it's not connected to the ISA bus as far as I know, thankfully)
I'm using Win98SE.
Well it's the same, have you enabled dma mode in 98 ? You have to go in the device manager and go to the hdd's properties to enable it.
Trying to identify old hardware ? Visit The retro web - Project's thread The Retro Web project - a stason.org/TH99 alternative
wrote:Well it's the same, have you enabled dma mode in 98 ? You have to go in the device manager and go to the hdd's properties to enable it.
There's no DMA checkbox for it since the chipset doesn't support DMA at all.
wrote:SiS supports PIO4, UMC supports PIO3 at best. (And no it's not connected to the ISA bus as far as I know, thankfully)
It seems you're right:
sorry for off topic
could you please take a photo of motherboard (area with voltage regulator ) ? thank you in advance
Some items for sale 😀
https://docs.google.com/spreadsheets/d/1YNG8R … dit?usp=sharing
This board can't overclock AMD 5x86 at all...
wrote:sorry for off topic
could you please take a photo of motherboard (area with voltage regulator ) ? thank you in advance
@RiP
i am appreciated for your help 😀
Some items for sale 😀
https://docs.google.com/spreadsheets/d/1YNG8R … dit?usp=sharing
