3DMark
3DMark is the latest version of this hugely-popular synthetic benchmark. Making use of DX11 features such as tessellation, compute shaders and multi-threading, it provides modern-day results and is available as a free download.
The shortcomings contained in the GTX 950 architecture are most keenly felt when the GPU is modestly clocked, as is the case with the PNY. Spending an extra £20 or so brings the more potent GTX 960 into play.