if it aint broke...

4 replies [Last post]
gethinc
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Joined: Sep 3 1999

I just installed an IBM 25gb drive into my system (a p2 350 on asus p2b, 196mb). It all went fine thanks to the advice from this BB. Thanks.

My proplem is this: I ran diskbench and was getting a read time of 12.4 MB per second. (And a similar write time). I ran the IBMATA 66 utility, to disable ata66, and it dropped to 3.4 MB/sec, so I then went back and re-enable ATA66 and it stayed at 3.4 MB/sec.

Can I undo this? Or will I have to re-install the whole disk? Urgh.

Any advice would be appreciated.

Gethin.

gethinc
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Joined: Sep 3 1999

Whoops. I just re-diabled ata66 and now its gone to 12.7 MB/sec. (Is this normal for this drive?)

My timer check is only getting 975. Can anyone tell me what this means?

BTW: I used IBM's EZdrive to install the drive - it made it extremely simple.

Geth.

RichardJ
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Joined: May 7 1999

Your 3.4 MB/s speed suggests that DMA mode is not enabled in Windows. This means Windows did not detect the drive as supporting any DMA mode. If the drive actually supports DMA 33, and the BIOS and Windows recognise this, you should continue to get around 12 MB/s. It seems your system works quite happily with the drive supporting DMA 66, though whether it's actually running at 33 or 66 we don't know, and it will not make a measurable difference anyhow.

12 - 13 MB/sec is probably the physical throughput limit of the drive. Don't be fooled by interface speeds, it's how fast the data gets on and off the disk platters that's important

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Richard Jones, http://www.activeservice.co.uk
Home of the MediaStudio Pro Tutorial

Richard Jones, http://www.activeservice.co.uk
Home of the MediaStudio Pro Tutorial - Edition 3 for MSP 7

gethinc
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Joined: Sep 3 1999

Thanks Richard,
DMA is switched on (at least in the device manager) - I did a clean install of win98. The only problem now is a windows protection fault, which microsoft says is due to a VXD conflicting with about twenty possible other things. Sigh. Next time I'll get a Mac.

Geth

Alan Roberts at work
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Joined: May 6 1999

Just for the record, I have an IBM 25G drive, and MotoDV reports 18.5 to 19.4 MB/s on capture, so the native drive's plenty fast enough.