Ubisoft's DRM isn't exactly known for its gentle, loving caress in matters near and dear to PC gamers' hearts, but the latest tightening of the cuffs seems a bit overkill-ish even by Ubi's standards. In attempting to review Anno 2070's performance on a range of hardware configurations, Guru3D made an extremely disappointing discovery: The second the site switched out a GTX 580 for a GTX 590, Anno demanded another, separate activation. On top of that, the game gives you a whopping three whole activations to work with, so think carefully before spelunking around in your machine's brittle innards.
I've fired off a mail to Ubisoft asking whether this is an intentional piece of extra armor plating for its DRM Voltron, or merely a glitch the publisher plans on patching out. Fingers crossed for the latter, though precedent's not exactly on our side.