Acer Altos 500 Series User Manual page 58

USB Host Controller
This parameter lets you enable or disable the USB controller on board. When
enabled, it activates the USB function of the system. When disabled, it deactivates
the function. The default setting is Disabled.
USB Legacy Mode
This function, when enabled, lets you use a USB keyboard in DOS. Set this to
Disabled to deactivate the USB keyboard function in DOS.
SMBus Interrupt (IRQ9)
The System Management Bus (SMBus) is used to control and get information from
devices on a motherboard. The system management software uses SMBus
hardware and software interfaces to access the information about the devices
attached to the SMBus. The default setting is Disabled.
Altos 500 Series User's Guide