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.
A boost in core speed provides a seven per cent increase over a stock 650 Ti Boost. The fatter front-end of a GTX 660, meanwhile, means that, in our opinion, no partner-clocked Boost is going to be able to match it in this synthetic benchmark.