This updated part promises to deliver significantly higher clockspeeds while running at lower voltages than the current Radeon HD 7970. The new GHz edition will reportedly be clocked at 1100MHz, 175MHz more than the Radeon HD 7970, while running at 1.020V, compared to 1.175V of the Radeon HD 7970. You can expect the launch by the end of the month or early July. Pricing is unknown.
Tahiti XT2, or Radeon HD 7970 GHz Edition, will ship with a core clock speed of 1100 MHz, 175 MHz faster than the HD 7970. The GPU core voltage of Tahiti XT2 will be lower, at 1.020V, compared to 1.175V of the Tahiti XT. It's unlikely that AMD will tinker with memory clock speed, since Tahiti already has a 384-bit wide GDDR5 memory interface, which gives it 264 GB/s memory bandwidth at 1375 MHz (5.50 GHz effective). According to the source, the new SKU enters mass-production next week. So best case, it should reach markets by late-June or early-July.