Aux power depends on GPU. Saying a power supply with a single spec of WATTS ignoring what goes on for the combined 3.3v/5v rails and 5vSB rail is a mistake that may cost you everything when it frys everything. My advice for power supplies that work takes into account Safety and Engineering standards from UL/CSA/VDE IEEE, EPS12v 2.92 as well as published specifications for 80 percent efficient DELL OEM power supplies.  You get the spec right from the label as is the case for the unit below. 375W and up video cards usually use 2 X   8 pin connections. 2 connectors 12v 18 AMPS + 75W slot power =507W just for the video card.  USB3 ports can provide 5W up to 100W of 5v power depending on how many ports and what type they are.  5w per port is bare miniumum so if you have 8 of them thats 40W just for USB3 ports. 12v 18 amps max is the rating for the 6 or 8 pin molex connectors and is listed the same on the dell power supply label to meet UL 94v fire safety regulations. 75W comes from the slot.  75W comes from a 6 pin 150W comes from an 8 pin. Cards with a single six pin use 150W Cards with 8 pin can use 225 to 375W Cards with DUAL 8 pin and adapter for new MINI 12 pin require 850W minimum power supply that meets EPS 12v spec for 3.3v/5v combined power. [IMAGE]36 AMP 12v AUX pci power mini 12 pin [IMAGE]RTX 3XXX series need DUAL 8 pin 850W psu EPS 12v 2.92 miniumum[IMAGE]875W unit with 225W combined for 3.3v/5v rails[IMAGE]AUX POWER 6 and 6+2[IMAGE]SLOT POWER IS PER SLOT so the required power depends on how many slots 12v 18 AMPS is max spec for 8 pin connector. 2 X 18 AMPS is 432W AUX power + 75W Slot power = 507Watts Just for a video card.  
Would 10mm make much of a difference in depth?  I'm trying to find a compatible PSU to replace the OEM one. Thanks.
Aurora R7, PSU dimensions