AMD's recently released Open CL drives has given us something to think about. Among the new cards listed in the support sheet, including the fresh HD 5800 and HD 5700 series, the driver also mentions two HD5900 parts.

Frankly, we are not sure what to make of this. It is quite possible that AMD will brand the dual-GPU incarnations of HD 5850 and HD 5870 cards as HD 5900 series, dropping the previous X2 suffix, but this is merely speculation.

Obviously, the other option is that AMD has a new GPU in store, probably a tweaked Cypress to take on Nvidia's Fermi. The latter option sounds a bit less realistic.

The driver also lists upcoming Cedar and Redwood cards.