sorry for the late response, I don't check here very often. The So-Dimm I purchased was from G.Skill. again I must stress that running in this configuration is not supported, but for me on my FX516PM, its worked fine. Use at your own risk..... it gives you an 'odd' amount of memory total, because of the 8+32 config: 40GB.
G.Skill Model No: F4-3200C22S-32GRS