Hey Jonathan!
Sorry about leaving that out. I’m using UE 4.3 (vanilla release build) - Windows 7 - an Nvidia Titan Black with drivers 9.18.13.3788 released 5/19/2014. The machine has been out of the box for a week so you can expect not much has been done to it.
Let me know if you need any other information. Thanks for checking it out.
-Chris