NVIDIA's GeForce 337.50 Driver was said to address performance when running DirectX 11-based software. Now that it is out, multiple sources are claiming the vendor-supplied benchmarks are exaggerated or simply untrue.
Going alphabetically, Anandtech tested the R337.50 and R331.xx drivers with a GeForce GTX 780 Ti, finding a double-digit increase with BioShock: Infinite and Metro: Last Light and basically zero improvement for GRID 2, Rome II, Crysis: Warhead, Crysis 3, and Company of Heroes 2. Adding a second GTX 780 Ti into the mix helped matters, seeing a 76% increase in Rome II and about 9% in most of the other titles.
BlackHoleTec is next. Testing the mid-range, but overclocked GeForce 760 between R337.50 and R335.23 drivers, they found slight improvements (1-3 FPS), except for Battlefield 4 and Skyrim (the latter is not DX11 to be fair) which noticed a slight reduction in performance (about 1 FPS).
ExtremeTech, finally, published one benchmark but it did not compare between drivers. All it really shows is CPU scaling in AMD GPUs.
Unfortunately, I do not have any benchmarks to present of my own because I am not a GPU reviewer nor do I have a GPU testbed. Ironically, the launch of the Radeon R9 295 X2 video card might have lessened that number of benchmarks available for NVIDIA's driver, who knows?
If it is true, and R337.50 does basically nothing in a setup with one GPU, I am not exactly sure what NVIDIA was hoping to accomplish. Of course someone was going to test it and publish their results. The point of the driver update was apparently to show how having a close relationship with Microsoft can lead you to better PC gaming products now and in the future. That can really only be the story if you have something to show. Now, at least I expect, we will probably see more positive commentary about Mantle – at least when people are not talking about DirectX 12.
If you own a GeForce card, I would still install the new driver though, especially if you have an SLi configuration. Scaling to a second GPU does see measurable improvements with Release 337.50. Even for a single-card configuration, it certainly should not hurt anything.