The speed of your memory in this case *technically* will have no impact on your soundcard. However, DDR requires a DDR chipset, and the chipset is what's going to dictate your success. Does the ASUS DDR board use an SiS chipset? You need to find out which chipset and the revision (if applicable) so that you can speak with tech support properly, because that's what they'll need to know.
I know that at least one person on the board here uses that Asus AMD DDR board, but I'm not sure what soundcard they use (or who they are, hehe).
M-Audio cards do *seem* to be a bit touchy when it comes to chipsets by VIA and SiS, but I we haven't been hearing many, if any, complaints around here about the more recent sets.
Do you already have the board? If so, you might as well put DDR in there. Data flow is managed by the chipset and memory speed will technically have *no* impact on PCI devices (unless you're overclocking).
NOTE: there is still a chance that DDR vs SDR *could* have an impact on your soundcard due to a design flaw in the dma controller or something crazy like that... I'm just saying that I wouldn't worry about it. DDR isn't much more expensive anyhow, and if you buy from a good vendor you can always exchange it if there is a problem. Go with DDR if you've got the capability.
If you're still shopping for a motherboard and are worried about reliability, then you need to be asking specifically about the motherboard and chipset, not so much the type of memory you plan to use. FWIW, neither RDRAM or DDR SDRAM have proven to be anything but modestly better performers than good old SDRAM. Don't let SDR vs. DDR be the critical factor in your motherboard purchase.
Slackmaster 2000
