One of the major benefits for Nvidia's Pascal architecture is that they can achieve really high clock frequencies. The 16nm Pascal based GeForce GTX 1080 boosts over 1800 MHz. AMD will bake Polaris at 14nm and as some information found in the SiSoft Sandra database, they reach 1.27 GHz with Polaris 10.

The SiSoftware Sandra 2015 OpenGL benchmark entry (look it up here) was entered 3 days ago and allegedly shows an entry of a Polaris 10 sample at 1266 MHz. The chip is identified by its Hardware ID, 67DF: C7 and 67DF: C4. These are both Polaris 10 ASICs, one Pro and one XT model. 

The entry denotes once again 36 compute cores (Nvidia call theirs SMs), 36 x 64 shader processors per cluster would mean 2304 active shader processors. The entry also reveals 8 GB memory being clocke at 7.6 GHz running over a 256-bit, so that would be 243 GB/s It however is unclear if AMD opted for GDDR5 or GDDR5X.

Obviously this might be just a reference sample, AMD can still increase the clock frequency at launch, with that in mind it remains to be seen what we finally going to see from the red camp.