The 950 is much newer and better. Clock speed alone is meaningless. Newer gen CPUs are more efficient with their clock cycles, so even though they may appear "slower" they do more work with each cycle.
But that's only the tip of the story. Both of those CPUs use different sockets, so if you're going for one, does that mean you're looking for a new mboard as well? And if you're you're getting a new mboard, perhaps you're intending to build a whole new system? And if so, then you've got a lot more questions then just "which CPU is better."
The forum has a template when asking about new builds, so I'd look for that. If you give us what you're intending to use your computer for ( so here I'd assume gaming" ) what your budget is for parts, and what parts you already have, we can be of much more help.