Never played with a DOM module but do know there are Chipset/BIOS limits on many old boards where a CF card based drive is much slower than a real IDE harddrive. My guess is it is compatible with your board but cannot run at it's rated speed because the BIOS and controller have an issue how to talk with it compared to a real HD.

Linear verify is internal to the device, working within the buffer or something. It doesn't involve the interface, so it's no practical figure.

Sis496 so I assume it's a 486? ISA or VLB I/O card? Assuming the DOM can keep up and isn't trash, this speed is normal for an ISA I/O.
I doubt you can get 5+ MB/s with whatever disk on similar systems (without going SCSI or PCI)

You can improve the performance (if the hdd is good enough) with chipset driver.

i tried it on a umc8881 board and its equally slow, and so is the cf card. it displays pio4 mode but i feel its actually pio1 performance.
would it get better in windows98?

noshutdown wrote on 2020-08-04, 06:40:

i tried it on a umc8881 board and its equally slow, and so is the cf card. it displays pio4 mode but i feel its actually pio1 performance.
would it get better in windows98?

Does your BIOS offer "IDE block mode" and/or "IDE 32-bit access"? If yes, make sure that both options are enabled. The SiS496/497 chipset has an integrated VL IDE controller, and will translate 32-bit VL cycles into 16-bit IDE cycles. A lot of VL IDE interface chips (don't know about the 496, though) immediately double their throughput if you use 32-bit cycles.