Asus P5B DELUXE P5B Deluxe user's manual - Page 39

2.4 System memory 2.4.1 Overview The motherboard comes with four Double Data Rate 2 (DDR2) Dual Inline Memory Modules (DIMM) sockets. A DDR2 module has the same physical dimensions as a DDR DIMM but has a 240-pin footprint compared to the 184-pin DDR DIMM. DDR2 DIMMs are notched differently to prevent installation on a DDR DIMM socket. The figure illustrates the location of the DDR2 DIMM sockets: ® P5B Deluxe DIMM_A1 DIMM_A2 DIMM_B1 DIMM_B2 P5B Deluxe 240-pin DDR2 DIMM sockets Channel Channel A Channel B Sockets DIMM_A1 and DIMM_A2 DIMM_B1 and DIMM_B2 2.4.2 Memory configurations You may install 256 MB, 512 MB, 1 GB, and 2 GB unbuffered non‑ECC DDR2 DIMMs into the DIMM sockets. • You may install varying memory sizes in Channel A and Channel B. The system maps the total size of the lower-sized channel for the dual-channel configuration. Any excess memory from the higher-sized channel is then mapped for single-channel operation. • Always install DIMMs with the same CAS latency. For optimum compatibility, it is recommended that you obtain memory modules from the same vendor. • Due to chipset resource allocation, the system may detect less than 8 GB system memory when you installed four 2 GB DDR2 memory modules. • This motherboard does not support memory modules made up of 128 Mb chips or double sided x16 memory modules. ASUS P5B Deluxe 2-13