This is under XP, my CD-ROM which supports Multi Word DMA 2 (according to
BIOS) refuses to use anything but PIO Only under XP.

This same CD-ROM with my last system (P3V4X) worked with DMA fine under XP.

Any help?

In article <bo20vq$163r4j$(E-Mail Removed)>, "Darkfalz"
<(E-Mail Removed)> wrote:

> This is under XP, my CD-ROM which supports Multi Word DMA 2 (according to
> BIOS) refuses to use anything but PIO Only under XP.
>
> This same CD-ROM with my last system (P3V4X) worked with DMA fine under XP.
>
> Any help?

There was a posting about this a while ago. If transfer errors are detected
on an IDE cable, the driver can shift down the transfer rate as it pleases.
A search in Google dug up a couple of links.

http://www.gmayor.dsl.pipex.com/cd_writer_udma_mode.htm
http://www.microsoft.com/whdc/hwdev/...e/IDE-DMA.mspx

Are you using the 40pin/80wire cable (thin wires versus the fatter
ones on the 40pin/40wire old style cable) ? Higher transfer rates
need the 80 wire cable, as 40 of the wires are ground signals that
improve signal transmission.

HTH,
Paul

> Are you using the 40pin/80wire cable (thin wires versus the fatter
> ones on the 40pin/40wire old style cable) ? Higher transfer rates
> need the 80 wire cable, as 40 of the wires are ground signals that
> improve signal transmission.

I'm using a 40 pin cable of course, because it's not an UDMA device.

> http://www.gmayor.dsl.pipex.com/cd_writer_udma_mode.htm

This tip worked great. I guess XP turned it off because I installed a game
from a rather poorly mastered CD-R that it struggled to read a bit. Doesn't
make much sense though because hard to read CDs have nothing to do with the
transfer protocol.

It seems like in some cases, when reading a badly burned/made disc, that the
drive takes too long to respond while trying to correct the errors, and
Windows decides that "The device failed to respond within the timeout
period" (as shown in Event Viewer). If that happens enough, Windows will
drop the UDMA mode or switch to PIO entirely.

--
Robert Hancock Saskatoon, SK, Canada
To email, remove "nospam" from (E-Mail Removed)
Home Page: http://www.roberthancock.com/


"Darkfalz" <(E-Mail Removed)> wrote in message
news:bo376i$17bna5$(E-Mail Removed)...
> > http://www.gmayor.dsl.pipex.com/cd_writer_udma_mode.htm
>
> This tip worked great. I guess XP turned it off because I installed a game
> from a rather poorly mastered CD-R that it struggled to read a bit.
Doesn't
> make much sense though because hard to read CDs have nothing to do with
the
> transfer protocol.
>
>