I have 3 GPUs but at startup CGminer load only GPU 0, I have to add the other 2 manually.
"C:\CGminer\cgminer-3.3.4-windows\cgminer-3.3.4-windows\cgminer.exe" --gpu-platform 0 -d 0 -w 256 -v 1 -I 19 -g 1 -l 1 --thread-concurrency 21712
-d 0 is telling it to only use GPU 0, so get rid of it