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.
Fewer compute units and an on-paper lower frequency do little to harm the R9 290's efforts in 3DMark. The card is almost as fast as a GeForce GTX Titan and, rather more ominously for Nvidia, is quicker than the GTX 780.