Yes, you can put 2 of these for a 24 monitor setup with just 2 cards
http://www.theinquirer.net/inquirer/news/1652779/powercolor-hd5970-display-outputs
http://www.theinquirer.net/inquirer/news/1652779/powercolor-hd5970-display-outputs

Quote from OrakelVanBrakel:
Any eyefinity card has 3 outputs. So if you use 4 cheap passively cooled <50USD ones, you also get 12 outputs. You'll save 1799USD and about 50 decibels of noise...
