Attached is a graph showing GPU load % and temp (C) versus time for an AMD W7100 workstation video card. This is a one hour video rendering from original MTS files using MainConcept MPEG-2 blu ray 1920x1080-60i, 25Mbps video stream on a Windows 10 x64 PC with no video FX inserted on Vegas 11. The data was captured using GPU-Z. I have no idea why and how Vegas choses to use the GPU (and when it does not), but thought some other forum members would find this useful.