TYAN TEMPEST I5000PW Manual page 25

Some chassis include plastic studs instead of metal. Although the plastic studs are usable,
Tyan recommends using metal studs with screws that will fasten the motherboard more
securely in place.
Below is a chart detailing what the most common motherboard studs look like and how
they should be installed.
TIP: Use metal studs if possible, as they hold the motherboard into place more securely
than plastic standoffs.
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