I am having the exact same issue with Adobe AE CC 2014. It’s not just while rendering, when working within a comp, previewing frames is extremely slow (even at half and third resolution).
I checked to make sure ray-tracing is off and it is. The comp settings are set for classic 3D.
I know it’s just this version because when I open the same projects in the last version of AE it works just fine.
I’m running it on a 2008 Mac Pro 8-core
Processor 2 x 2.8 GHz Quad-Core Intel Xeon
Memory 12 GB 800 MHz DDR2 FB-DIMM
Graphics NVIDIA GeForce 8800 GT 512 MB
Software OS X 10.9.4 (13E28)