you've gotta remember though kerry, that ultra dma isn't enabled by default on dma66 or dma33 hard drives. No wait a minute, it is but the running speed isn't set properly. it's usually set to dma33 and you have to use a utility to enable dma66 for some stupid reason. You do under windows any way. not sure about linux. Shaun.. "We realise we have a problem with communication. However, we're not going to discuss it with our staff." EMAIL: shauno at goanna.net.au ICQ: 76958435 YAHOO ID: blindman01_2000 IRC NICK/SERVER: |3|1ndm4n on #aussiefriends on www.jong.com:6667 On Sun, 3 Jun 2001, Kerry Hoath wrote: > You may also find that certain drives want to go into udma66 > which makes sense since that is their fastest powerup dma mode. Now if you don't happen > to have a UDMA66 cable, then you can experience dma timeouts or crc errors, > because Linux thinks the drive is in superfast mode, the drive does too but the signals on the cable > are getting corrupted due to the lack of conductors in the cable. > UDMA 66 has 80 conducters and normal ide has 40, although both only have 40 pins. > > I found that with my Quantum 30gig drive, I couldn't enable dma reliably > unless I had an UDMA66 cable on the Via 82c586 controller. Some new > drives suck in pio mode providing a lack lustre 5 megabytes per second > but run at 15 megabytes when udma is enabled. > If anyone wants any more information on Linux and DMA/UDMA let me know under Linux, > sadly under Windows you'll have to ask Kirk Wood about the dark side :-) > > Regards, Kerry. > On Sat, Jun 02, 2001 at 04:53:14PM -0500, Kirk Wood wrote: > > First, understand why Windows 2000 doesn't complain about the DMA. If the > > drive times out twice (ever) then it no longer uses DMA ever. So it won't > > complain. It won't tell you. In fact, win winclows 98 they burried any > > indication that this had happened. It happens more often them many people > > realize. > > > > Having said that, if you didn't have DMA support compiled into the kernel > > you wouldn't get the errors. Yes, it must be compiled in if it is to be > > used. (DMA falls back to PIO in case of failure and PIO always remains > > available.) > > > > As for fixing this, it is either the motherboard or the drive. I know that > > doesn't help. You might check to see that DMA is turned on in the > > BIOS. (Linux will try anyway, winblows just acts like it is using DMA and > > doesn't really.) Otherwise try another DMA drive and see if the problem > > resolves. > > > > ======= > > Kirk Wood > > Cpt.Kirk at 1tree.net > > > > Nothing is hard if you know the answer or are used to doing it. > > > > > > _______________________________________________ > > Speakup mailing list > > Speakup at braille.uwo.ca > > http://speech.braille.uwo.ca/mailman/listinfo/speakup > > -- > -- > Kerry Hoath: kerry at gotss.net > alternatives: kerry at gotss.eu.org or kerry at gotss.spice.net.au > ICQ UIN: 8226547 > > _______________________________________________ > Speakup mailing list > Speakup at braille.uwo.ca > http://speech.braille.uwo.ca/mailman/listinfo/speakup >
