Chapter 2: Installation Support The H8DCE supports single or dual-channel, registered ECC DDR400/333/266 SDRAM. Both interleaved and non-interleaved memory are supported, so you may populate any number of DIMM slots (see note on previous page and charts on following page). The CPU2 DIMM slots can only be accessed when two CPUs are installed (however, the CPU2 DIMM slots are not required to be populated when two CPUs are installed). Populating two adjacent slots at a time with memory modules of the same size and type will result in interleaved (128-bit) memory, which is faster than non-interleaved (64-bit) memory.
Optimizing memory performance If two processors are installed, it is better to stagger pairs of DIMMs across both sets of CPU DIMM slots, e.g. fi rst populate CPU1 slots 1A and 1B, then CPU2 slots 1A, and 1B, then the next two CPU1 slots, etc. This balances the load over both CPUs to optimize performance. Maximum memory (two CPUs) : 32 GB for DDR266 and 16 GB for DDR400/333. If only one CPU is installed, maximum supported memory is halved (16 GB for DDR266 and 8 GB for DDR400/333). Figure 2-2. Side and Top Views of DDR Installation To Install: Insert module vertically and press down until it snaps into place. The release tabs should close - if they do not you should close them yourself.
Note the notch in the slot and on the bottom of the DIMM. These prevent the DIMM from being installed incorrectly. To Remove: Use your thumbs to gently push each re- lease tab outward to release the DIMM from the slot. 2-5