Hey, I realize I'm late to the party - and that you likely already returned this unit...but one thing I wanted to point out about this PSU (and any other units in general):
There's a small red switch, near where the AC input cable plugs in, that switches input voltage from 220-110vac. If you see a switch like this, that is an automatic "DO NOT BUY" (IMO, of course). Any power supply worth a darn made in pretty much the last 10-15 years will have what's called "Active PFC" (Power Factor Correction). If a PSU has active PFC, it won't have that red switch. If it has the red switch, it doesn't have active PFC.
Units that lack active PFC are typically very cheap, low-quality power supplies (a 'passive' PFC design is cheaper to produce, which is why those units are built that way).
This is why I say if it has the switch (meaning no active PFC), don't buy it.
Just my $.02 for any other who might read this; hope it helps