New PSU-Won't boot

Was there any instructions for the PSU as to where to plug in the cables or a chart or label for the connectors on the PSU?

Jim

No. It's a Corsair AX850 and there seems to be no difference as to where things go although most things will only fit in one socket. I'm looking at the manual but it doesn't say what socket is for what.

I could try that tomorrow Gazz, I don't think I have a Display port connector but I can certainly take out the hard drives. Should I still get a BIOS display if I do that?
I've been at this for about 11 hours now I'm knackered

Thanks for all your help everyone. I'm losing concentration so I'm going to stop now. I'll be back tomorrow and try some of the things you have suggested.
Hopefully, you'll still be around to help. Good night and thanks for your patience, John:)

John, found this on TigerDirect. It is a little hard to see until you click on the pix, but TD outlined where the Mod Plugs go:

Corsair CMPSU-850AX AX850 Power Supply - ATX, Modular, 850 Watt, 80+ Gold Certified, 120mm Ultra-Quiet Fan at TigerDirect.com

Just thought I'd have a last look before crashing out. Thanks Anak:). That's really useful. I've got it bottom mounted upside down but I think I've got it right.
My 24 pin ATX socket on the mobo goes to the 10 pin power socket bottom left and the 18 pin socket above it. The 12 volt mobo connector goes to the 12 pin power connector bottom right.
The 12 pin next to that takes a double four (or 6 if needed) socket into the GPU
There are two output to sata sockets for the hard drives and the optical drive and I've put them next to the 18 pin socket, although I think they will fit it all 5 of those 6 pin sockets.
So. That seems ok to me. What do you think.?
I'm off to bed now. Thanks very much again

Your welcome!

Okay for me too, but since I have a few more arc minutes (astronomical term) because I'm here in the States, and I need to hit the sack. I'll have a look around to see if I can find anything on AX850s and GA-EX58-UD5P/UD5 Motherboards, and how they are connected.

That sounds right to me. If you can't get it fixed, I would swap the PSU's in your two rigs to see if it is the PSU or the motherboard that is bad.

Jim

There are a number of things with this Corsair PSU that makes it very difficult for me to recommend it. They all concern the power cables and the arrangement of sockets on the PSU into which they plug.

Let's start with the main ATX cable. This is a standard 20/24 pin connector, so why is it split into 2 connectors of 18 and 10 at the PSU end, giving 28 pins in total? The standard molex and floppy connectors are another. These are 4 pin, so why is the PSU end 6 pin? Same for SATA connectors - device end 5 pin, PSU end 6 pin. And the cable that gave you the initial problem, the 4+4 pin ATX12V one. Why does it have 12 pins on the PSU end of the cable?

The manual is about as much use as a chocolate fire guard, as it provides no information whatsoever on how to attach the cables correctly to the PSU.

I concur with Jim's suggestion of swapping PSUs to see if that works.