You can put this in the Stickie.
AMD CPUs based on Athlon 64 architecture can be found with the following socket types:
Socket 754:
Used by early Athlon 64, some Sempron models and Turion 64. Their memory controller is single channel, meaning that the CPU accesses memory at 64-bit rate.
Socket 939:
Used by Athlon 64, Athlon 64 FX and Athlon 64 X2 processors. Their memory controller is dual channel, meaning that the CPU accesses memory at 128-bit rate, if two memory modules are used.
Socket 940:
Used by early Athlon 64 FX and Opteron processors. Their memory controller is dual channel again, meaning that the CPU accesses memory at 128-bit rate, if two memory modules (or an even number of memory modules) are used. They require ECC memory type.
It's a general tidbit on AMD CPUs.