AB221A HP 512 MB DDR-SDRAM Memory Pair

AB221A is the 512 MB DDR-SDRAM memory pair, two 256 MB DIMMs, for the HP Integrity rx1600 and the HP Integrity rx1620. The 256 MB DIMM spare is A6967AX, a 266 MHz, PC2100 DDR-SDRAM module. The pair also carries the title HP rx1600 512 MB 2x256 MB DIMMs SDRAM Memory.

It is the smallest of four pair options: AB222A (1 GB of 2x512 MB), AB223A (2 GB of 2x1 GB) and AB224A (4 GB of 2x2 GB). Memory goes in as pairs of DIMMs with equal density, and 512 MB is the minimum memory for either server.

Each server has eight DIMM slots and takes up to 16 GB, which is eight 2 GB DIMMs. To support chip sparing, identically sized DIMMs are loaded in quads, sets of four.

Every pair is loaded across both memory buses, one DIMM on each bus, for maximum bandwidth and performance. Total memory bandwidth is 8.5 GB/s, split across two 4.25 GB/s buses, and open page memory latency is 80 nanoseconds.