Aurora R8, 850W PSU failure

Looking for some advise.  Earlier this week while my son was playing a game the computer went off. Completely dead appeared to be the power supply so brought it into Best Buy for a free check and sure enough a dead power supply on a PC just over a year old. Best Buy advised would be at least 3 months before they would likely be able to repair it based on how long it's been taking to get parts advising me to contact Dell. 

The failed power supply was the 321-BEPU Alienware(TM) 850 Watt Multi-GPU Approved Power Supply with High Performance Liquid Cooling. Such high performance that it burned out in just over a year. Appears the warranty is only 1 year which is the hardware warranty which came with the PC. Quite poor for a PSU. Anyone else have issues with these units failing? Any recommendations for a replacement PSU which will fit the case and components and also power the DVD drive?  

I contacted DELL's support and they advised they have no replacement 321-BEPU PSU's currently available. Great support on a year old PC.  Appreciate any advise on getting this unit running again.