CD-R/RW and DMA

River · Mar 22, 2007, 06:32 PM

what is the maximum DMA transfer mode you can achieve with a cd-r/rw unit, with an 80 conductor cable? mine is at transfer mode DMA-2, is that the highest?

i've googled and can't really find anything definite.

thanxz
River~

Judas · Mar 22, 2007, 07:30 PM

anything beyond that is i think kinda pointless... considering that theoretical maximum speeds even with a 20x DVD drive reading or writing will just touch udma 2's max.

However there are some models that from within XP or vista, show UDMA mode 4 supported and working. Is there a speed difference? Well possibly no more then say 2-5% max. Still limited by the type of media used.

I mean we can get SATA1 DVD-RWs now, but that's to be expected as IDE is phased out, that's UDMA 6 mode isn't it?

River · Mar 22, 2007, 07:34 PM

Judas, hey, thanxz for the info, i was just curious. just finished sticking a 2nd hard drive in to my unit, and checked the dma settings for the hard drives, they are at 5, and noticed the cd-r/rw was at 2, even with 80 connector, and thought got me to thinking if it would be higher. but, if as you say, the speed difference would be minimal, and is now limited by ide being phased out, makes sense.

River~

Judas · Mar 22, 2007, 08:48 PM

i know that alot of cd-rw's or dvd drives or any optical drive usually won't even run UDMA 2 if you use anything other then a 80pin cable... if you use a 40 pin, usually the highest speed is a multi-word DMA2 mode which isn't true ultra DMA.... it's kinda a mix between PIO mode 4 (which is fairly slow and resource hogging) and udma...

all the machines i build have 80pin connections to the optical drives.

Mar 22, 2007, 06:32 PM	#1
River -=[DHzer0point Team]=- Join Date: Apr 2003 Location: Salem, Oregon Posts: 174 Rep Power: 0	CD-R/RW and DMA what is the maximum DMA transfer mode you can achieve with a cd-r/rw unit, with an 80 conductor cable? mine is at transfer mode DMA-2, is that the highest? i've googled and can't really find anything definite. thanxz River~ __________________ Dell Dimension 4550 P4, 2.4ghz, 533mhz FSB 1gig ddr ATI Radeon 9700TX, 128mb DDR 17" digital flat panel Harmon Kardon speakers SoundBlaster Live 5.1 Logitech wireless keyboard/mouse Intel Pro/100 VE Windows XP Pro "did you want cheese with that?"

Mar 22, 2007, 07:34 PM	Thread Starter #3
River -=[DHzer0point Team]=- Join Date: Apr 2003 Location: Salem, Oregon Posts: 174 Rep Power: 0	Judas, hey, thanxz for the info, i was just curious. just finished sticking a 2nd hard drive in to my unit, and checked the dma settings for the hard drives, they are at 5, and noticed the cd-r/rw was at 2, even with 80 connector, and thought got me to thinking if it would be higher. but, if as you say, the speed difference would be minimal, and is now limited by ide being phased out, makes sense. River~ __________________ Dell Dimension 4550 P4, 2.4ghz, 533mhz FSB 1gig ddr ATI Radeon 9700TX, 128mb DDR 17" digital flat panel Harmon Kardon speakers SoundBlaster Live 5.1 Logitech wireless keyboard/mouse Intel Pro/100 VE Windows XP Pro "did you want cheese with that?"