For official information you'll likely have to wait another week or two but TechPowerUp already got its hands on some leaked benchmarks and clockspeed details of AMD's Radeon R9 290X. The company's new flagship reportedly has a 800MHz core, 4500MHz GDDR5 memory, 512-bit memory bus and a memory bandwidth of 288GB/s (which of lower than the >300GB/s that AMD mentioned last week). The source also says there's no dynamic overclocking feature, but the chip can lower its clocks, taking load and temperatures into account.
Performance-wise the Radeon R9 290X seems to be ahead of the NVIDIA GeForce GTX Titan in most tests. All benchmarks were performed with a resolution of 5760 x 1080 pixels though.
Among the tests run on the card include frame-rates and frame-latency for Aliens vs. Predators, Battlefield 3, Crysis 3, GRID 2, Tomb Raider (2013), RAGE, and TESV: Skyrim, in no-antialiasing, FXAA, and MSAA modes; at 5760 x 1080 pixels resolution. An NVIDIA GeForce GTX TITAN was pitted against it, running the latest WHQL driver. We must remind you that at that resolution, AMD and NVIDIA GPUs tend to behave a little differently due to the way they handle multi-display, and so it may be an apples-to-coconuts comparison. In Tomb Raider (2013), the R9 290X romps ahead of the GTX TITAN, with higher average, maximum, and minimum frame rates in most tests.