All,
It has been alluded to in multiple places in this thread, but I thought it worth pointing out specifically...
Many people report issues when using a combination of DIMMs adding up to 32GB. I too ran into this problem (and I am part of the development team). What I discovered is that my DIMMs, while supporting an XMP profile above 1333MHz, recommend only one DIMM per channel when using this profile. This is a subtle thing; not very obvious unless you are specifically looking for it. In my case, I purchased DIMMs from Crucial's Ballistic Tracer series -- specifically because they include thermal sensors in the DIMMs (they are compliant with the Thermal-Sensor-On-DIMM (TSOD) specification). I found that I could run at 1600MHz only when I installed one DIMM per channel. If I installed two DIMMs per channel, I always ended up running at 1333MHz. Only by happenstance, when I was running AIDA64, I saw a status message indicating that only one DIMM per channel was supported in the XMP profile. Bottom line, it is worth checking for this limitation so you understand what is going to be possible with a specific set of DIMMs...
...Scott
