Hardware Reference
In-Depth Information
Repeat the same steps to enable DMA transfers for any additional hard drives and ATAPI
CD-ROM drives in your computer. Restart your computer after making these changes.
Note
If your system hangs after you enable this feature, you must restart the system in Safe mode
and uncheck the DMA box.
If your drive is a parallel ATA model that supports any of the Ultra-DMA (also called
Ultra-ATA) modes, you need to use an 80-conductor cable. Most motherboards refuse to
enable Ultra-DMA modes faster than 33MBps if an 80-conductor cable is not detected.
Note that these cabling issues affect only parallel ATA drives. If your drives are Serial
ATA (SATA) models, these cabling issues do not apply.
Depending on your Windows version and when your motherboard chipset was made, you
must install chipset drivers to enable Windows to properly recognize the chipset and en-
able DMA modes. Virtually all motherboard chipsets produced since 1995 provide bus-
master ATA support. Most of those produced since 1997 also provide UltraDMA support
for up to 33MHz (Ultra-ATA/33) or 66MHz (Ultra-ATA/66) speed operation. Still, you
shouldmake surethat DMAisenabled toensure youare benefiting fromthe performance
it offers. Enabling DMA can dramatically improve DVD performance, for example.
Interface
The drive's interface is the physical connection of the drive to the PC's expansion bus.
The interface is the data pipeline from the drive to the computer, and you shouldn't min-
imize its importance. Four types of interfaces are normally used for attaching an optical
drive to your system:
•
SATA (Serial ATA)
—The SATA interface is the same interface used by most recent
computers for connecting their hard disk drives. With many recent systems featuring
support for as little as one PATA (Parallel ATA) drive, but support for eight or more
SATA drives, most optical drive vendors are now producing SATA versions of their
drives.
ComparedtosimilarPATAopticaldrives,SATAdrivesfeatureequalperformance,but
are easier to install because it is not necessary to jumper the drive for master/slave or
cable select.
•
PATA (Parallel AT Attachment)
—The PATA interface is the same interface most
older computers use to connect to their hard disk drives. PATA is sometimes also re-
ferred to as ATA (AT Attachment) or IDE (Integrated Drive Electronics).
