Asus P4RD1-MX - Manual (Page 24)

1-12 Chapter 1: Product introduction
1.7.2 Memory Configurations
You may install 64MB, 128MB, 256 MB, 512 MB and 1 GB unbuffered
non-ECC DDR DIMMs into the DIMM sockets using the memory configurations
in this section.
• For dual channel configuration, the total size of memory module(s)
installed per channel must be the same (DIMM A1=DIMM B1).
• Installing DDR DIMMs other than the recommended configurations
may cause memory sizing error or system boot failure. Use any of
the recommended configurations in Table 1.
• 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 limitation, DIMM modules with double-sided x16
memory chips are not supported in this motherboard.
• Visit the ASUS website for the latest DDR 400 MHz (FSB 800/533)
Qualified Vendors Lists.
Table 1 Recommended memory configurations
For dual-channel configuration, the total size of memory module(s) installed
per channel must be the same to ensure optimum performance.
Channel Sockets
Channel A DIMM_A1
Channel B DIMM_B1