Actually enabling DMA through device manager is not enough. U should go through BIOS setup and change DMA setting Auto-> Enable (by default it usually Auto). Depend upon BIOS type some times DMA Controller may placed under Advance Feature, but usually you’ll found in same drive menu under Standard Feature.
You have not maintain the no. of IDE Drive using. However if u r using one IDE HDD as a Primary Master and optical drive as Primary Slave, then buy separate IDE cable & plough your optical drive as Secondary Master (You may choose 80.wared-Ultra DMA cable for better res.).
And finally if you are using Windows XP there nothing to be worry your Device Manager automatically choose the right option!
You can update your firmware for better performance. Make sure downloading the correct firmware according to your ACTUAL drive model!!! And flash it correctly.
Otherwise you’ll start the above procedure with a NEW ONE!!!!
SONY official firmware can found on:
*sony.storagesupport.com/dvdrw/firmware.htm