The Radeon HD 7700 series scaled well in Crossfire, achieving about 80% efficiency. The cards choked in King Arthur II, which was only released in late January and will presumably receive better driver support soon. If you exclude that title, the HD 7770 saw an 85% boost when doubled up and the HD 7750s averaged 86% faster.
That sounds great on paper, but is it enough to consider the Crossfired HD 7700 series a valid option for budget-minded gamers? Unfortunately, no -- or at least not yet.
We'll start with the HD 7770. At $320, the dual-card configuration is 60% more expensive than the $200 HD 6870 while delivering 39% more performance. Likewise, the duo is 33% pricier than the $240 GeForce GTX 560 Ti while offering only 29% better results on average.
Although we estimate the dual HD 7700s are a tad cheaper and faster than a lone HD 6970 ($350), we'd rather take the minor performance hit and deal with a single card solution.
At $220, the HD 7750 Crossfire configuration is a slightly better value than the HD 7770s -- just as we found when testing them as single cards. The dual HD 7750s are priced around 5% lower than the GTX 560 Ti and in our testing, the Crossfire solution performed about 3% better. But again, for such a minor gain, we'd rather opt for the single-card solution. It'd take a healthy 10% difference or more for that stance to change as running multiple GPUs in Crossfire or SLI comes with extra baggage.
As illustrated in King Arthur II, multi-GPU setups don't always play nice with new games. It's common for AMD or Nvidia to add the necessary profiles after a game launches, meaning you'd have to play with a single card until then anyway.
Beyond compatibility issues, multi-GPU configurations tend to require more space, produce more heat and consume more power. For those reason, we believe they should usually be reserved for those wanting to achieve maximum performance with high-end cards.
We recognize that mainstream cards can sometimes leverage Crossfire or SLI to deliver an incredible value. Sadly, that's not the case with the HD 7770 or 7750. As we found in our first review, the HD 7700 series is priced against superior products with a wider memory bus, more bandwidth and more complex core designs. We hope this changes when Nvidia's next-generation cards arrive in the coming weeks and months. Until then, we can still only recommend a single HD 7750 for HTPC-like purposes.