Cooler Master has given us a list of Haswell compatible power supplies, which it has assembled using its own testing methodology.
Earlier, we heard that Intel's Haswell CPUs might have problems with certain less expensive or older power supplies because the CPUs would be too efficient for them. A number of manufacturers have already released their lists of compatible power supplies, and now Cooler Master has given us a list of their own. In fact, the list is rather interesting. Since there is no official testing procedure, Cooler Master has gone and decided that adding a case fan to increase the idle load should solve the problem. Instead of using the 1 W idle that Intel's 4th Generation processors are supposed to achieve, the addition of a case fan means the usage would be a little more, just enough to keep the system stable. The power savings, however, would only be equal to around 2-3 W, unlike the 5 W you'd experience with an Ivy Bridge systems.
Due to this custom testing methodology (and creative solution to increase rail load), Cooler Master has given us a list with all of its power supplies that it's currently producing, and says that that they are all Haswell compatible.
Of course, disabling the C6 and C7 states would also make the PSUs compatible. Sadly, Cooler Master hasn't given us a list of power supplies that support Haswell CPUs with the C6 and C7 states enabled.