Today, NVIDIA announce that the 6600 will be able to run in SLI. It wouldn't be difficult to guess that both cards do not need any BRIDGE to interconnect the cards to run in SLI mode.
According to various source, it seems that the new driver allows one to run two cards in SLI mode. In fact, even 6600GT, 6800GT and even the 7800GFX can run in SLI mode without the bridge. Although it works, there is a drop in performance. In fact, I heard that 6200 can be run in SLI too.
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