TYAN S8212 User Manual page 29

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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