Lenovo NeXtScale nx360 M4, Installation And Service Manual

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System reliability guidelines
To help ensure proper system cooling and system reliability, make sure that the following requirements
are met.
• Each of the drive bays has a drive or a filler panel and electromagnetic compatibility (EMC) shield
installed in it.
• Each of the power-supply bays has a power supply or a filler installed in it.
• If the compute node has redundant power, each of the power-supply bays has a power supply installed in
it.
• There is adequate space around the compute node to allow the compute node cooling system to work
properly. Leave approximately 50 mm (2.0 in.) of open space around the front and rear of the compute
node. Do not place objects in front of the fans. For proper cooling and airflow, replace the compute node
cover before you turn on the compute node. Operating the compute node for extended periods of time
(more than 30 minutes) with the compute node cover removed might damage compute node components.
• You have followed the cabling instructions that come with optional adapters.
• You have replaced a failed fan within 48 hours.
• You have replaced a hot-swap fan within 30 seconds of removal.
• You have replaced a hot-swap drive within 2 minutes of removal.
• You have replaced a failed hot-swap power supply within 2 minutes of removal.
• You do not operate the compute node without the air baffle installed. Operating the compute node
without the air baffle might cause the microprocessor to overheat.
• Microprocessor socket 2 always contains either a socket cover or a microprocessor and heat sink.
• You have installed the fourth and sixth fans when you installed the second microprocessor option.
Handling static-sensitive devices
Use this information to handle static-sensitive devices.
Attention: Static electricity can damage the compute node and other electronic devices. To avoid damage,
keep static-sensitive devices in their static-protective packages until you are ready to install them.
To reduce the possibility of damage from electrostatic discharge, observe the following precautions:
• Limit your movement. Movement can cause static electricity to build up around you.
• The use of a grounding system is recommended. For example, wear an electrostatic-discharge wrist
strap, if one is available. Always use an electrostatic-discharge wrist strap or other grounding system
when working inside the compute node with the power on.
• Handle the device carefully, holding it by its edges or its frame.
• Do not touch solder joints, pins, or exposed circuitry.
• Do not leave the device where others can handle and damage it.
• While the device is still in its static-protective package, touch it to an unpainted metal surface on the
outside of the compute node for at least 2 seconds. This drains static electricity from the package and
from your body.
• Remove the device from its package and install it directly into the compute node without setting down the
device. If it is necessary to set down the device, put it back into its static-protective package. Do not
place the device on the compute node cover or on a metal surface.
• Take additional care when handling devices during cold weather. Heating reduces indoor humidity
and increases static electricity.
Chapter 5
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Removing and replacing components
91