the Cooler Master EP PSu's are one of the many reasons CM gets such a horrible rep for PSU's. They're overrated, mislabled, and overpriced piece of turds that are barely better than generic PSU's that blow up all the time.
Get at least Corsair CXV2 units or Antec EA / Neo Eco units or hell even OCZ psu's at the minimum.
P.S. Corsair does not 'make' any units but buys them from manufacturers such as seasonic, cwt, flextronics etc which makes them to specifications that corsair or other companies demand.