Hexus takes a look at CrossFire and SLI dongle-less / bridgeless performance:
We'll spare you the trauma, however, and focus on just one aspect of multi-GPU rendering that could be seen as an annoyance: bridges and dongles. With all that bandwidth on PCI-Express-enabled motherboards, how is it we still need to provide a link between our two graphics cards before they'll work harmoniously? Be it internal SLI bridge or external CrossFire dongle, sometimes it can prove problematic, especially for the downright lazy.
Bridgeless and dongle-less multi-GPU rendering isn't exactly new. We've seen it on lower-end SLI and CrossFire solutions, but now it's starting to rear its head higher up the product ranges, where the lack of a dedicated inter-card link might have a bigger impact. Shall we see if it does? OK then!