Boo-Yah! 8GB (2x4GB) works in pro.

Thanks, Chirpa. I will try with one module tonight and see if I have better luck. Do you know if I should use one slot over another when using one DIMM?

** UPDATE **

Well after some more testing it does look like this memory is indeed incompatible. I couldn't get it to boot with either stick in the slot furthest from the CPU which, according to Gary's first post, should offer the best shot at getting it to work. I wish I could isolate what makes that Patriot memory work, but I'm just not that much of a hardware enthusiast.

I was hoping to avoid dropping ~$200 on the Patriot memory since that would make it applicable for Sander's first law of hardware upgrades which states the failure the overall system increases exponentially with each expensive upgrade specific to said hardware, but I guess I will have to swallow that pill if I want to use this system as a home lab.