I'm guessing gaming. You can get an idea of the 950m vs 960m by checking GPUCHECK.com and notebookcheck.

It's not an issue with the CPU yet. Here's a prior comment about CPU power.
"Our tests demonstrate fairly little difference between a $225 LGA 1155 Core i5-2500K and a $1000 LGA 2011 Core i7-3960X, even when three-way graphics card configurations are involved. It turns out that memory bandwidth and PCIe throughput don't hold back the performance of existing Sandy Bridge-based machines. "
http://www.tomshardware.com/reviews/gaming-cpu-review-overclock,3106-4.html

In those systems you are driving one GPU so for today, your better GPU wins at game results but for say non GPU accelerated apps, the CPU wins.