AB561A HP 16GB Chip Spare PC2100 DDR Memory Quad

AB561A is a 16-GB chip spare PC2100 DDR-SDRAM memory quad for the HP 9000 rp3440, made of four 4 GB DIMMs. The 4.0 GB DDR-SDRAM DIMM spare for it is AB475-69001, which comes with an 8-slot restriction on the rp34x0 and rx2620.

With 4 GB DIMMs the rp3440 supports one configuration only, eight 4 GB DIMMs, which means two AB561A quads. Four 4 GB DIMMs are not supported. The eight DIMMs go in the first eight slots and the remaining four slots stay empty, and 32 GB (8 x 4 GB) is the maximum memory of the server. The next highest amount is 24 GB, twelve 2 GB DIMMs.

The rp3440 has twelve DIMM slots and takes DDR SyncDRAM DIMMs with ECC and chip spare protection. DIMMs beyond the first four go in quads of equal density, and memory is loaded in the sequence marked on the system board. Each quad is loaded across both memory buses, two DIMMs on each bus. Total memory bandwidth is 8.5 GB/s over two 4.25 GB/s buses.