IBM BlueGene/L/P/Q Compute Cards

First we got a BlueGene/L compute card. Eventually we got another set of BlueGene/L, /P and /Q compute cards.

BlueGene/L

BlueGene/L Compute Card consists of two processor chips and 18 DRAM chips. The DRAM is a standard DDR SDRAM from Samsung with P/N K4H511638B-TCCC (32M×16). There are no termination resistors on the memory bus.
IBM BlueGene/L Compute Card

There are another set of DRAM patterns on the back of the Compute Card.
IBM BlueGene/L Compute Card (back)

Two connectors with dimension of 6-by-18 (108-pin) connect the card to the rest of the system.
IBM BlueGene/L Compute Card (socket)

A conventional heatsink is glued on top of the compute chip.
IBM BlueGene/L Compute Card (top)

BlueGene/L, BlueGene/P and BlueGene/Q Compute Cards

Three generations of BlueGene Compute Cards. The heatsink is glued to the chip on BlueGene L and P.
BlueGene L P and Q
The BlueGene/L compute card pictured here have all DRAM soldered. The one that I got another day did not have them.
BlueGene L P and Q
BlueGene L P and Q

A heatsink is fixed to the BlueGene/Q Compute Card using six T10 screws. Blue TIM is visible.
BlueGene L P and Q