Enabling DMA Mode Transfers (PATA Only)
Depending on what level of DMA your hard disk and interface support, enabling DMA transfers may or may not increase disk performance noticeably, but enabling DMA is always worthwhile, because it greatly reduces the burden that PIO transfers place on the processor. If a computer has 75% CPU utilization using PIO transfers, that same computer using DMA transfers may provide the same or better disk performance at perhaps 1.5% CPU utilization. With multitasking operating systems, those extra free CPU ticks translate into faster system response.
To use DMA transfers, the hard drive, BIOS, and chipset must explicitly support DMA, and the operating system must have DMA drivers installed, loaded, and enabled. All ...
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