Combining AC and DC PSUs is not supported and triggers a mismatch. You can refer below link for details [URL] 
Hi, I recently made a purchase of a MMHVDC power supply for my system. the original PSU I'm using is a 1100w EPP with P/N Y26KX. it has a IEC c13 jack. The MMHVDC PSU I purchased by accident was also capable of 220VAC. can those two PSU be used in a same system? MMHVDC PSU P/N T94HP. I did try both PSU in a same system and it works. would this be a good idea? also two PSU came with different rev of firmware. is it safe to upgrade the firmware with both PSU plugged in? I do noticed in the update firmware page clearly showed do not mix PSU with different wattage. But, in my case both PSU are 1100W just different P/N. Thanks
R730xd with different power supply