Following the trend of other manufacturers, after AMD officially announced 1 GHz variants of their HD 4890, it looks as though XFX will be releasing a Black Edition HD 4890 with the famed 1 GHz GPU clock speed. It would appear that XFX are still using the reference design, other than a change to red DVI ports as seen on some of their other ATI based graphics card, and the reference cooler with an XFX Black Edition sticker.

AMD is preparing yet another performance-mainstream Radeon HD 4000 series SKU. The Radeon HD 4790 finds lineage from the Radeon HD 4890, currently AMD's fastest GPU. The RV790 GPU will be given a new set of specifications and memory configuration, to yield an SKU that performs better than the Radeon HD 4770, and slightly better than HD 4850. It beats us as to why it is positioned in the HD 4700 series, and not say "Radeon HD 4860", but we are too late to comment on that.

Specifications-wise, the RV790 core runs at 600 MHz, slightly lower than the RV770 in Radeon HD 4850 (625 MHz), but its performance increment over it comes from the use of GDDR5 memory. The GPU makes use of a 256-bit wide GDDR5 memory interface. It handles 512 MB of memory clocked at 800 MHz (3200 MHz effective). Being based on the RV790, it is pin-compatible with any existing HD 4890 PCB. Price-wise, it is expected to sit between the HD 4850 and HD 4870.

Through the magnificent improvement in cooling system and materials, MSI R4890 Cyclone SOC has made a breakthrough of core speed 1 GHz limitation.
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