User`s manual

4.2.4Integrated Peripheral
4.2.4.1 Onchip IDE Device
4.2.4.3.1 IDE HDD Block Mode
Block mode is also called block transfer, multiple commands, or multiple sector
read/write. If the IDE hard drive supports block mode (most new drives do),
select Enabled for automatic detection of the optimal number of block read/writes
per sector the drive can support.
4.2.4.3.2 IDE DMA Transfer Access
This item could allows you to enabled/disabled the IDE UDMA transfer function
and only use PIO mode