GeForce GTX 295
The Nvidia GeForce GTX 295 is a monster of a card. It boasts two GPUs sandwiched on two boards, using internal SLI to connect them together. Because the connection is internal you don't need a SLI capable motherboard, and it only takes up a single PCI-express slot (though it will block access to the adjacent slot as well). The GTX 295 was released by Nvidia in late 2008 to combat AMD's Radeon HD 4870x2 which was the most powerful card at that time, and in comparisons became the clear winner in most games. Being the top performing single card available, the GTX 295 has a price tag to match it's performance: it currently retails around $530.
Complete Specs:
Core: 2x G200b
Manufacturing Process: 55nm
Stream Processors: 480 (2x 240)
Memory: 1792MB (2x 896MB) GDDR3
Memory Interface: 2x 448-bit
Core Clock: 576MHz
Memory Clock: 1998MHz