Installing System Components 1294 Reinstall expansion-card riser 2. See "Replacing Expansion-Card Riser 2."5 Install all expansion cards in the expansion-card slots. See "Installing anExpansion Card."6 Close the system. See "Closing the System."7 Reconnect your system and peripherals to their electrical outlets, and turnon the system.System MemoryYour system supports DDR3 registered DIMMs (RDIMMs) or ECCunbuffered DIMMs (UDIMMs). Single and dual-rank DIMMs can be 1067-or 1333-MHz, and quad-rank DIMMs can be 1067-MHz.The system contains 18 memory sockets split into two sets of nine sockets,one set for each processor. Each nine-socket set is organized into threechannels of three memory sockets per channel. The first socket of eachchannel is marked with white release levers.The maximum memory that is supported on your system varies according tothe types and sizes of memory modules being used:• Single-rank and dual-rank RDIMMs of sizes 2-GB, 4-GB, and 8-GB(when available) are supported for a total of up to 144 GB.• Quad-rank RDIMMs (two per channel) are supported for a total of up to96 GB.• 1-GB and 2-GB UDIMMs are supported for a total of up to 24 GB.General Memory Module Installation GuidelinesTo ensure optimal performance of your system, observe the following generalguidelines when configuring your system memory.NOTE: Memory configurations that fail to observe these guidelines can cause yoursystem to halt at startup without any video output of system messages.• RDIMMs and UDIMMs cannot be mixed.• No more than two UDIMMs can be populated per channel.• Except for memory channels that are unused, all populated memorychannels must have identical configurations.
