HP D2954-60001 - ECC memory expansion board with 8 additional SIMM sockets - ECC Memory Expansion Board (with 8 Additional SIMM Sockets) Retail
HP D2971-63006 - ECC memory expansion board - Has 12 additional SIMM sockets - ECC Memory Board (with 12 SIMM Sockets) - Plugs into the Top of the System (Mother) Board (2 Can be Used) Retail