Chimpzilla's Radeon R9 290 and 290X review copies appear to be performing better than retail versions.
Techreport penned a review which said that AMD upended the high-end graphics market by offering performance competitive with Nvidia's existing products at substantially lower prices. The R9 290X captured the overall GPU performance crown, wresting it away from the GeForce GTX 780 and Titan.
However, some of its readers said that Radeon R9 290X cards bought at retail do not seem to perform as well as the review units AMD supplied to the press.
The retail R9 290-series cards had the same basic hardware and specifications as the review samples, but at least some retail R9 290-series cards seemed to operate at lower clock speeds.
Techreport got on the blower to AMD which investigated and found that the fans on some retail cards were not spinning as fast as expected, and the reduced cooling capacity resulted in lower clock speeds.
http://news.techeye.net/chips/retail...-review-copies
Retail Radeon chips still go slower than review copies
6th December 2013, 07:40
Retail Radeon chips still go slower than review copies 
