Dual-Channel Mode Population Rule - MSI 990FXA GAMING User Manual

Memory
These DIMM slots are used for installing memory modules.

Dual-Channel mode Population Rule

In Dual-Channel mode, the memory modules can transmit and receive data with two
data bus channels simultaneously. Enabling Dual-Channel mode can enhance system
performance. The following illustrations explain the population rules for Dual-Channel
mode.
DIMM1
DIMM3
Important
• DDR3 memory modules are not interchangeable with DDR2, and the DDR3
standard is not backward compatible. Always install DDR3 memory modules in
DDR3 DIMM slots.
• To ensure system stability, memory modules must be of the same type and density
in Dual-Channel mode.
• Due to chipset resource usage, the system will only detect up to 31+ GB of memory
(not full 32 GB) when all DIMM slots have 8GB memory modules installed.
DIMM1
DIMM2
DIMM3
DIMM4
DIMM1
DIMM2
DIMM3
DIMM4