MSI ATX Motherboard G52-MA00362 - Manual (Page 43)

Hardware Setup
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ISA (Industry Standard Architecture) Slot (optional)
The ISA slot provides one 16-bit interface that are used to add
expansion card to the computer.
CNR (Communication & Networking Riser) Slot
The CNR slot allows you to insert the CNR expansion cards. CNR
is a specially designed network, audio, or modem riser card for ATX
family motherboards. Its main processing is done through software and
controlled by the motherboard’s chipset.