Hi Jamie,
In the process of finding my CPU usage problems I found I could not
compile Gem on the g5 from the terminal:
g++ -c -fPIC -g -O2 -freg-struct-return -O3 -fno-builtin -falign-loops=16
-funroll-loops -ffast-math -faltivec -I.. glsl_fragment.cpp -o
glsl_fragment.o
2Hgz g5 dual 10.3.9 is the machine.