From: http://www.logicalincrements.com/haswell/

Corsair

From: http://www.corsair.com/en-us/blog/2013/may/haswell-compatibility-with-corsair-power-supplies

  According to Intel's presentation at IDF, the new Haswell processors enter a sleep state called C7 that 
  can drop processor power usage as low as 0.05A. Even if the sleeping CPU is the only load on the +12V rail, 
  most power supplies can handle a load this low. The potential problem comes up when there is still a 
  substantial load on the power supply's non-primary rails (the +3.3V and +5V). If the load on these 
  non-primary rails are above a certain threshold (which varies by PSU), the +12V can go out of spec 
  (voltages greater than +12.6V). If the +12V is out of spec when the motherboard comes out of the 
  sleep state, the PSU's protection may prevent the PSU from running and will cause the power supply 
  to "latch off". This will require the user to cycle the power on their power supply using the power 
  switch on the back of the unit.