Crucial 2GB Single DDR3 1066 MT/s (PC3-8500) CL7 Unbuffered UDIMM 240-Pin Desktop Memory Module CT25664BA1067 at Amazon.com
A-Tech 4GB (2 x 2GB) RAM for HP Compaq 4000 Pro & 6000 Pro - (Small Form Factor & Microtower) - DDR3 1066MHz PC3-8500 Non-ECC DIMM Memory Upgrade Kit at Amazon.com
Elpida 2GB 204-Pin PC3-8500S DDR3 Sdram at Amazon.com
Elpida 2GB PC3-8500S DDR3 SDRAM SO-DIMM Memory at Amazon.com