Hi - For the last 24 hours I've been blowing my brains out trying to find a solution to my problem!  Basically, I cannot write to dual layer discs.  

I have a Dimension 9200 with a Dual Layer +/- DVD RW Drive.  I traced the problem back to it being that I have to enable "DMA" and to do so, I need to go into my Device Manager and open the sub-category "IDE ATA/ATAPI Controllers".  Problem:  I don't have that sub-category!  I tried reinstalling the firmware but the flash utility couldn't find the drive.   Moments ago, I found a forum post saying that if you have "RAID" enabled in the BIOS (which I do) you won't have "IDE ATA/ATAPI Controllers" within your device manager - instead, it is replaced by "SCSI and RAID Controllers" (which I DO have!).  However, I cannot enable DMA from this sub-category.  I tried to install the Intel Ultra ATA Storage Driver, which someone else who had a similar problem was advised to do, to no avail and I have tried everything but one: changing, in the BIOS, "RAID" to "RAID Autodetect/ATA".  But when I do this, it warns me that my OS may not boot up and may result in my having to reinstall windows - something I would rather not do... again.

My question is: if I change "RAID" to "RAID Autodetect/ATA" in the BIOS, will things go wrong?!!!  Obviously there is no guarantee either way, but what are the chances of it working?  

I have 3 HDDs installed in my computer: 2x 250GB working in a RAID 0 configuration - these contain the OS [XP Professional x64 - PC came with Vista Ultimate x64 which I got rid of], and 1x 500BG HDD which has no OS.

Any help would be greatly appreciated!

Thanks! 

P.S.  Please let me know if I am, again, barking up the wrong tree!!!