Qlogic InfiniPath, Install Manual

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2 – Hardware Installation
Safety with Electricity
2-4 IB0056101-00 C
Q
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ACPI needs to be enabled
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MTRR mapping needs to be set to “Discrete”
MTRR (Memory Type Range Registers) is used by the InfiniPath driver to enable
write combining to the InfiniPath on-chip transmit buffers. This improves write
bandwidth to the InfiniPath chip by writing multiple words in a single bus transaction
(typically 64). This applies only to x86_64 systems.
However, some BIOSes don’t have the MTRR mapping option. It may be referred
to in a different way, dependent upon chipset, vendor, BIOS, or other factors. For
example, it is sometimes referred to as "32 bit memory hole", which should be
enabled.
If there is no setting for MTRR mapping or 32 bit memory hole, please contact your
system or motherboard vendor and inquire as to how write combining may be
enabled.
ACPI and MTRR mapping issues are discussed in greater detail in the
Troubleshooting section of the
InfiniPath Interconnect User Guide .
NOTE: BIOS settings on IBM Blade Center H (Power) systems do not need
adjustment.
You can check and adjust these BIOS settings using the BIOS Setup Utility. For
specific instructions on how to do this, follow the hardware documentation that came
with your system.
2.2
Safety with Electricity
Observe these guidelines and safety precautions when working around computer
hardware and electrical equipment:
1. Locate the power source shutoff for the computer room or lab where you are
working. This is where you will turn OFF the power in the event of an emergency
or accident. Never assume that power has been disconnected for a circuit.
Always check first.
2. Don’t wear loose clothing. Fasten your tie or scarf, remove jewelry, and roll up
your sleeves. Wear safety glasses when working under any conditions that
might be hazardous to your eyes.
3. Shut down and disconnect the system’s power supply from AC service before
you begin work, to insure that standby power is not active. Power off all attached
devices such as monitors, printers, and external components. Note that many
motherboards and power supplies maintain standby power at all times.
Inserting or removing components while standby is active can damage them.
4. Use normal precautions to prevent electrostatic discharge, which can damage
integrated circuits.