New PSU (EVGA Supernova G3) for Aurora R5 (issues with GPU_PWR)

Cass-Ole figured this out and provided this info to me ... I am just passing it on to you.

Yes, it must be connected.
 
That Aurora (R5 or R6) on-motherboard GPU / PCIe power connector is set up to be identical to a CPU Header, with x4 12v top / x4 ground bottom wires.
 

Most after-market PSUs in the 850w+ range, the front panel should have x2 CPU 8pin ports & come with x2 CPU cables in the pouch

If we pretend we bought an EVGA 850, it would have x2 CPU modular ports, with x2 CPU cables (x2 4+4s most likely) in the pouch, and we'd power R5 CPU + GPU_PWR header with both of the CPU cables.

Notice the latch and where the black grounds are. It obviously accepts a CPU power-plug  (not a PCIe 8-pinner video card power plug). Due to keying, I suspect you would have to try really hard to force the wrong plug into that socket and get it to seat properly. There would also be lots of magic smoke escaping.
 
Yes, the stock Aurora 850watt PowerSupply provides a white 8-pin CPU plug for this GPU_PWR header , but only has 6 wires installed in it ( x3 12v top / x3 ground bottom). This should be sufficient power/amps for all single-card installs and most SLI setups.

Is yours liquid cooled? Mine is an air cooled unit, I have already replaced my stock CPU cooler with a liquid cooler, that made it slightly quieter when under load. But the PSU was the real problem, which is what I am currently trying to replace.

For your interest, I have attached a photo the PSU's specs below: 

Thanks a lot for your answer.

I came across a few of Cass-Ole's answers on these forums, and yet even with your very helpful answer I am still not sure what to do. The EVGA Supernova G3 750W I bought has 2 CPU 8-pin outputs on the PSU, as you can see in the screenshot attached below.

Should I therefore connect one of these CPU outputs to the GPU_PWR connector on the motherboard? The PSU came with a few 8 pin to 4+4 pin cables. Assuming I do need to connect the CPU2 output to the GPU_PWR input on the motherboard, should I connect one 4 pin socket to GPU_PWR or both (4+4 pin)?

My stock PSU had a cable connected to GPU_PWR where only 6 pins were actually wired.

I just replaced my standard 850w PSU (because the stock PSU is incredibly loud)

Interesting.
 
The 850w one pre-installed in my Aurora-R6 is quiet like normal.

Great, thanks a lot for the help once again. I will give it a try soon.

As for your previous reply regarding the liquid cooling - the PSU is also liquid cooled when you order the R5 with liquid cooling (and not just the CPU) am I right? It was a real mistake I made ordering the Aurora without liquid cooling, but at the time I thought that the air cooled version would be fine in terms of noise. To be honest, the CPU fan only made noise when gaming, and was perfectly OK when just idling along or doing light work. But the PSU was shockingly bad constantly, and really needed changing. When I configured it I ordered the 850W PSU, perhaps the 460W PSU is much quieter.

Thanks again!

1. Is yours liquid cooled?   2. But the PSU was the real problem, which is what I am currently trying to replace.

1. Yes, with stock Alienware cooler
 
2. I don't have a pic of the full label yet, or know the rating classification.
 
Your original stock 850w one appears to be DPN: 0N1WJD

Sure no problem.
 
No, just the CPU. The 850w power supply I got appears to be a conventional fan cooled model.
 
If you search the forums, you will see users reporting "loud fans" in Aurora-R5 over the years. As you know, there are various fans in the Aurora-R5 but the quantity/ make/ model (and even control) of these fans varies depending on config.
 
I'm not aware of how Dell resolved these issues nor have I really been following it too close.
 
I can say that my Aurora-R6 does NOT have this problem. At idle, it's virtual silent. At max gaming ... you can hear the fans pick-up a bit (but it is still quieter than my Aurora-R1). But this is expected since it's not an iPad or phone. I think it's mostly the single fan on the stock GTX-1070.

Yes, I saw reviews where people said their machines were basically silent. So yeah, it may be just bad luck that I ended up with a bad/cheap PSU. I was thinking about just changing the PSU's fan actually, but I wasn't sure how the fan is connected internally, or whether I'd need to solder wires.

Oh and I can confirm that connecting the CPU 8 pin from the PSU to the the GPU_PWR 8 pin connector on the motherboard worked. My GPU is now running as normal!  

I can confirm that connecting the CPU 8 pin from the PSU to the the GPU_PWR 8 pin connector on the motherboard worked. My GPU is now running as normal!

Excellent