The Haswell launch gets just a little more complicated each day, with the latest wrinkle being that standard ATX power supplies that conform to the ATX 2.3 standard may not actually be capable of supporting Haswell's extremely low power sleep states. The result has been power supply manufacturers scrambling to see if their power supplies can handle Haswell's requested 0.05A on the 12V rail as opposed to the ATX 2.3 minimum's 0.5A.

Both Corsair and Sea Sonic have been rigorously testing their power supplies to determine which ones definitely can handle Haswell's C6/C7 states, and both have a list of power supplies which are certified to run Haswell, and in the case of Corsair and their substantial portfolio, which power supplies should be able to handle Haswell with no problems.

Starting with Sea Sonic, the following power supplies are certified Haswell ready:

Corsair is a little bit more complicated. Certification testing is ongoing, but the following power supplies have been guaranteed to be fully compliant with Haswell:

Corsair's validation efforts continue on the following models (predominately legacy), which they say are "likely compatible" but are not confirmed yet:

If you're looking to make the jump to Haswell next month, the best thing you can do is likely going to be to watch the homepage and support page of your vendor of choice. Haswell will still work just fine with most power supplies, but you may have to disable these lower power sleep states to maintain stability.