Don't worry FLOPS, I am not suggesting you have sold me a faulty piece of equipment at all, I have been using this site long enough to understand that people here are genuine and when they put an object up for sale it's always functioning, so I have no qualms or issue. It is, what it is, I am going to purchase a MicroATX PSU along with an adapter, and we'll see what occurs after that.
This task has been a learning experience for me, I am not going to lie, I have come from an Amiga 1200 (which I lovingly store under my bed in a drawer) but have been wanting an Amiga 4000D for a very long time (20+ years) I just love and have always loved a big box Amiga, so I am very happy to have one. I understood that I would need to get a PCI bridgeboard along with RTG and network, this had always been my plan, but I knew it would come at a cost...
I could have got an A3000, an A2000 or an A1500, but they weren't the ones I wanted, I wanted to go as late as possible. (AGA non-wedge machine) And I am happy I did. OK, the front bezel could do with brightening a bit as it's a bit yellow, but that's a plan for the summer, when the weather is better in the UK.
I have no way of knowing what the 5 volt rail is actually putting out, I am a techie by trade, but I am not an electrician...

We'll see how things pan out afterwards.
On the question of CSPPC's - Do you know if you have left the flash on the accelerator as GREX compatible or is back in non-GREX mode? (I won't flash it, but just asking the question)
Thanks
Colin