Chapter 4: AMI BIOS
4-11
Air Flow
This item allows the user to set the desired speed of air ow to the DIMM mod-
ules. Each increment is one mm/sec. The default is [1500]. Press "+" or "-" on
your keyboard to change this value.
Altitude
This item allows the user to specify the altitude of the location where the com-
puter is used. For Tylersburg-EP platforms, system memory thermal solution
is derated up to 900m. To comply with CPU specications, BIOS will attempt
to adjust and correct DIMM velocity based on the altitude where the system is
located in order to improve DIMM thermal performance. Altitude is dened as the
number of feet above the sea level where the computer is located. The options
are Sea Level or Below, 1~300 (above-), 301~600 (above-), 601~900 (above-),
901~1200 (above-), 1201~1500 (above-), 1501~1800 (above-), 1801~2100
(above-), 2101~2400 (above-), 2401~2700 (above-), and 2701~3000 (above-)
the sea level.
DIMM Pitch
Use this feature to specify the distance of physical space between each DIMM
module. Each step is in 1/1000 of an inch. The default is [400]. Press "+" or "-"
on your keyboard to change this value.
High Performance Event Timer
Select Enabled to activate the High Performance Event Timer (HPET) that produces
periodic interrupts at a much higher frequency than a Real-time Clock (RTC) does in
synchronizing multimedia streams, providing smooth playback and reducing the de-
pendency on other timestamp calculation devices, such as an x86 RDTSC Instruc-
tion embedded in the CPU. The High Performance Event Timer is used to replace
the 8254 Programmable Interval Timer. The options are Enabled and Disabled.
Intel VT-d
Select Enabled to enable Intel's Virtualization Technology support for Direct I/O VT-d
by reporting the I/O device assignments to VMM through the DMAR ACPI Tables.
This feature offers fully-protected I/O resource-sharing across the Intel platforms,
providing the user with greater reliability, security and availability in networking and
data-sharing. The settings are Enabled and Disabled.
Intel I/OAT
The Intel I/OAT (I/O Acceleration Technology) signicantly reduces CPU overhead
by leveraging CPU architectural improvements, freeing resources for more other
tasks. Available options are Disabled and Enabled.
