Aren't 30 MB/s good enough for a 486-class computer? I barely get more with mine.

Return 0; wrote on 2024-02-09, 10:16:

I decided to start a new topic. Although I found a lot of such threads, I didn't get an answer in any of them. My problem concer […]
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I decided to start a new topic. Although I found a lot of such threads, I didn't get an answer in any of them. My problem concerns DMA in win98se, namely several cases:
1. PODP5V 83 computer, shuttle hot-433 + PCI Promise ultra66: no DMA checkbox in device manager, yet atto bench shows ~30MB/s peak
2. K6-3+ computer, VIA MVP3
a) Promise ultra66 same as point 1.
b) onboard IDE, DMA checkbox checked -30MB/s
3. athlon K7, GA7VX onboard IDE DMA checkbox checked -45MB/s

Questions:
1. How to make sure that DMA is pre-enabled when there is no checkbox for Promise, is this normal?
2. in each case, the CPU usage when copying files is 100%, only on K7 + Win XP it drops to 30%, does this mean that DMA does not work after all and it cannot be clearly determined based on the AttoBench results?

There is no checkbox...

Promise FAQ

"Q: Where is the "DMA" checkbox for the HDDs on the Ultra66 in Win9x?

A: The "DMA checkbox" that you’re referring to will not appear for any HDD connected to the Ultra66. Since the card’s sole purpose in life is to provide your computer with an ATA/66 interface, the feature is automatically, and always, enabled. As long as the Ultra66 BIOS detects the HDD as "Mode 4", the ATA/66 timing will be used. You can check this by running a benchmark program on the HDD. We recommend using the CoreTest utility that you can download from ftp://ftp.promise.com.

NOTE: You should run CoreTest from a true DOS environment. To do this, reboot your computer using a boot disk. Now you can switch to the HDD and run CoreTest."

Yes, it is clear answer. I will check this benchmark program.