Asus CROSSHAIR IV EXTREME User Guide - Page 94

Block (Multi-Sector Transfer) M [Auto] Enables or disables data multi-sectors transfers. [Auto] When set to [Auto], the data transfer from and to the device occurs multiple sectors at a time if the device supports multi-sector transfer feature. [Disabled] When set to [Disabled], the data transfer from and to the device occurs one sector at a time. PIO Mode [Auto] [Auto] Allows automatic selection of the PIO (Programmed input/output) modes, which correspond to different data transfer rates. [0] [1] - [4] Set the PIO mode to Mode 0, 1, 2, 3, or 4. DMA Mode [Auto] DMA (Direct Memory Access) allows your computer to transfer data to and from the hardware devices installed with much less CPU overhead. The DMA mode consists of SDMA (single-word DMA), MDMA (multi-word DMA), and UDMA (Ultra DMA). Setting to [Auto] allows automatic selection of the DMA mode, or you can select from the following options: [SWDMA1] [SWDMA2] [MWDMA0] [MWDMA1] [MWDMA2] [UDMA0] [UDMA1] [UDMA2] [UDMA3] [UDMA4] [UDMA5] SMART Monitoring [Auto] [Auto] Allows automatic selection of the S.M.A.R.T (Smart Monitoring, Analysis, and Reporting Technology). [Enabled] Enable the S.M.A.R.T feature. [Disabled] Disable the S.M.A.R.T feature. 32Bit Data Transfer [Enabled] [Enabled] Sets the IDE controller to combine two 16-bit reads from the hard disk into a single 32-bit double word transfer to the processor. This makes more efficient use of the PCI bus as fewer transactions are needed for the transfer of a particular amount of data. [Disabled] Disable this function. 3-18 Chapter 3: BIOS setup