Win7, DVD-RW stuck in PIO mode

[entropy]

Hi, thanks in advance to anybody that can help me, i'm stumped.
Running windows 7 ultimate x86 on my Inspiron 6000 laptop (see specs)
My optical drive recently stopped working, it was a CDRW/DVD-ROM drive that came stock with the computer. I removed the drive, thinking i could replace it with one of the many spare optical drives i have laying around, but i've tried 3 different drives so far
GWA-4082N DVDR/RW/CDRW
19771282-59 DVD+RW/CDRW
GMA-4082N DVDRAM DVDRW/CDRW
all three of these physically fit into the bay, seem to (!) connect properly and they work just fine, except i'm stuck with PIO on that channel. DVD playback is choppy, slow, etc.
and ____DMA cannot be enabled for primary channel 1.____ I click the box, but it is not enabled and is unticked the next time i look.
i have tried updating MB drivers, Firmware, no luck.
tried uninstalling one, then both channels + rebooting, then the storage controller.
also updating controller drivers did nothing for me.
the much-appraised RegHack to delete Master/SlaveIDChecksum values will not work for me, as i am using Win7 and those registry entries are non-existent.
tried dell's "pushDMA" tool from the website. also no luck.
my HD runs in DMA ultra 5 but on channel 1 my DVD drive(s) will only utilize PIO mode.
also, all 3 drives run in DMA mode perfectly when installed in an HP system.

somebody help! is it because my drivers aren't fully compatible with 7?
is it because the optical drives are from HP and Dell really hates that kinda s***?
can someone maybe point me toward a registry entry to modify to force DMA?

i don't think i have to explain what a pain in the ass PIO mode is.

 

[entropy]

nobody? i'm thinking it has something do do with my drivers not being fully compatible with win7.. only way to know for sure is to switch HD's and install XP.. see if the problem goes away. if i still have the issue, then it can at least be narrowed down to a hardware compatibility issue