We have finally entered the mid-range and mid-range to low-end segments and one of their members is the R7 260X video card which is built around the Bonaire GPU which we have reviewed some while ago: Radeon HD 7790.
When looking at both Radeon HD 7790 and the 260X we will see the technical specification similarities like 896 Shader Units, the 128-bit memory bus, 16 ROPs and the same transistor count. AMD has packed this time 2048MB of GDDR5 RAM and increased the clocks a little bit more for both GPU (1100MHz vs 860MHz) and memory (1625MHz vs 1500MHz). The HIS R7 260X iPower IceQ X2 card does not come with higher frequencies but it was custom-built in order to have a better overclocking potential.
The PowerTune function is now available on the full range so the GPU clock gets modified depending on power draw, heat and performance factors. Eyefinity has been also updated to V2 DDM, with the ability of 5x1 landscape and custom multi-monitor resolutions. Also, with the new series we are permitted to use the Eyefinity feature without the need of a DisplayPort adapter.
If the card provides for example two DVI ports and one HDMI, we can use all three to set up Eyefinity.
The R7 260X comes with the Tensilica DSP which enables TrueAudio function, which is also available on the high-end 290 and 290X offerings. Surprisingly we have found out that it was available on the first incarnation of Bonaire too, but was not enabled.
On the 260X we can find three DSP cores which are dedicated to the HiFi2 EP Audio and employ Tensilica’s Xtensa ISA. The DSP is fully programmable which is very good for the programmers. Each core comes with 32KB of instruction and data cache along with 8KB of scratch RAM. One fast interface connects the DSPs to 384KB of shared internal memory which is organized in 8KB banks. Also, up to 64MB of buffer is addressable via a low-latency bus interface shared with the display pipeline.
Mantle is a new API introduced with the latest seriers, which gives the game developers direct access to the GPUs by using the Graphics Core Next architecture. AMD has recently clarified that Mantle creates for PC a development platform which is similar to the one for the consoles, which already offer low-level APIs, close-to-metal programming, easier development and more. By creating a more console-like developer environment, Mantle improves time to market, reduces development costs and allows more efficient rendering and ultimately improves performance for gamers.
DirectX 11.2, which is coming with Windows 8.1 is compatible with the new series.
The main attraction of the latest DirectX seems to be Tiled Resources, which exposes AMD’s partially-resident textures via DirectX and we are also dealing with hardware-managed virtual memory for GPU.