Phoenixminer is possible stale shares which GPU - >> total ?? and gpu 1 /? gpu2 /? gpu3 /? etc. It is easier to change settings of the GPU that causes the most stales.

It does this already. x,y,z are assigned stale shares per each GPU that caused it.
GPU 1 shares 10/x, GPU 2 shares 10/y, GPU 3 shares 10/z