A few key observations on the Crossfire of two HD 5970s need to be made. First, if you don’t have a powerful CPU, two of these video cards will likely not be GPU bound in any way shape or form but CPU bound. The HD 5970 is a powerful card by itself; two of them in CrossfireX mode are the most powerful solution on the market today, bar none. Two HD 5970s require a big PSU, with a maximum power requirement of 588 Watts just for the video cards alone. ATI has a list of Certified Power Supplies on their website and I would suggest a minimum of 850W for two of these 5970s. The Cooler Master 1000W PSU we use for testing worked like a charm with consistent performance across tests without power problems. If you are in the market for the best performance, features and aren’t concerned about the cost or availability, two HD 5970s in CrossfireX mode IS the solution for you today.