The Radeon R9 290X
AMD’s reference Radeon R9 290X is exactly as long as Radeon HD 7970 (11”) and similarly two expansion slots wide. Even the 75 mm centrifugal fan looks like it carried straight over.
Also familiar is the little switch on the card’s top edge. Previously, that might have been used to control maximum clock rates, enabling a minor boost for an extra bit of performance. Given those PowerTune changes we just covered, though, that wouldn't make sense. Instead, that's the switch to toggle between Quiet and Uber mode.
The fan shroud is clearly updated, and I’ve already heard feedback from Tom’s Hardware staffers who really like the more sweeping red and black design. I remain partial to Nvidia’s metal shroud and polycarbonate window though, particularly at this very high-end price point. There are plenty of GeForce GTX 780s with third-party coolers, but a great many ship with the reference ID I wrote about in The Story Of How GeForce GTX 690 And Titan Came To Be. It’d be great to see AMD step up with something similarly inspired.
Despite similar dimensions, Radeon R9 290X is clearly based on a different PCB than AMD’s Tahiti-based cards. Most obvious is the lack of CrossFire connectors. Because Hawaii features an xDMA engine, CrossFire traffic is carried over the PCI Express bus, eliminating the need for those pesky cables. It appears improbable that an aftermarket cooler designed for 7970 would work on R9 290X.
AMD is staying quiet on maximum board power, but claims that R9 290X should push up to 250 W in typical gaming scenarios. Realistically, because PowerTune is constantly making changes, it’s pretty difficult to nail down peak consumption. We recorded a range, though, and found a peak that spanned from 225 to 295 W. Given one eight- and one six-pin auxiliary power connector, plus a 75 W PCI Express slot, those numbers are within the 300 W you probably wouldn’t want to exceed.
The R9 290X cards we received all had two dual-link DVI ports, a full-sized HDMI output, and one DisplayPort connector. Its Hawaii GPU features an updated display controller though, which includes a third independent timing generator. So, although the flagship board comes equipped with one less display output than the R9 280X we recently reviewed, you can actually hook up six screens operating at different resolutions and timings to the R9 290X with an MST hub.
Hawaii’s new display controller will also enable the 600 MHz pixel rates needed to support upcoming single-stream Ultra HD displays at 60 Hz. As you know, currently, the only way to drive a 4K screen is through two HDMI ports or one DisplayPort 1.2 output with MST support. These correspond to a pair of 1920x2160 tiles that come together as a 2x1 Eyefinity array. Next-generation scalars will make 3840x2160p60 possible without tiling—they’ll simply require higher pixel clocks. Radeon R9 290X can do it for sure, but AMD isn’t certain whether its older display controllers will.