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DMA with Asus 52x???

PostPosted: Tue Nov 05, 2002 3:57 pm
by rikb7
Hi

I'm using Win XP Pro SP1 at the moment and have realised there's a problem with my Asus 52x CD-ROM.

I've noticed a large decrease in speed from the Asus drive recently, although I'm not sure if it's connected with the installation of Service Pack 1 or not.

Using Nero Infotool it tells me that the Asus doesn't have DMA enabled.
I have an LG 8204B as master and the Asus as slave on IDE channel 2.
In device manger, the transfer modes on both slave and master are set to "DMA if available"
It shows the current transfer modes as:

LG burner - multi-word DMA mode 2
Asus 52x - PIO mode

is this right?

If so, how can I force the Asus to operate with DMA activated. When I first got XP I had a few problems getting things up and running but I managed it and got great results from both the Asus and the LG in Nero CDSpeed, so I know the Asus is capable of running with DMA enabled.
The graph in CDSpeed I get at the moment shows clearly that the Asus isn't working with DMA and the speeds are quite pathetic.

I have a feeling that the last time I had a problem I installed the lastest VIA 4in1 drivers which asked if I wanted to enable DMA when I installed them and that seemed to get things working well. However the latest 4in1s (4.43) don't give you the option, they just install the drivers automatically.

Any help would be much appreciated
Cheers
Rik

PostPosted: Tue Nov 05, 2002 4:41 pm
by dodecahedron
check out the FAQ:
Problems enabling DMA in Windows XP
for help enabling DMA.

PostPosted: Tue Nov 05, 2002 5:28 pm
by rikb7
Brilliant!

Thanks for the quick response - I had read the faq but wasn't sure whether my Asus was supposed to be in PIO mode or not so didn't try uninstalling just in case.

Anyway - my Asus is flying once again!

Thanks again

Rik
:)

PostPosted: Tue Nov 05, 2002 5:43 pm
by Ian
I really don't like the way XP handles DMA. If the OS senses that the drive is returning read errors (I forget how many before it does this), it will lower the UMDA mode. Essentially, if you get a bunch of errors, your drive eventually ends up at some PIO mode and running like crap. I wish there was a way to disable that.

PostPosted: Wed Nov 06, 2002 3:36 am
by dodecahedron
rikb7 wrote:I had read the faq but wasn't sure whether my Asus was supposed to be in PIO mode or not so didn't try uninstalling just in case.

it should be Multi-Word DMA mode 2.
that's the best (fastest) DMA mode that is not UDMA. so this is the best it can go.
(AFAIK the drive does not support UDMA).

PostPosted: Wed Nov 06, 2002 6:21 am
by rikb7
Device manager now shows the LG burner as Multi-word DMA mode 2 and the Asus as Ultra DMA mode 2. So it seems it does support UDMA

Either way - it's very very fast now!

I'll keep my eye on it though. It's interesting what Ian said about XP reverting to a lower transfer mode due to read errors. Nice of it to just do it without informing you!

PostPosted: Wed Nov 06, 2002 3:01 pm
by dodecahedron
rikb7 wrote:Device manager now shows the LG burner as Multi-word DMA mode 2 and the Asus as Ultra DMA mode 2. So it seems it does support UDMA

OK, my bad, the 52x Asus CDROM does support UDMA.
the LG does not so it's best is Multi-Word DMA mode 2.