If you pick 590 GBP it suggests the following mobo/gfx
ASRock H81M-HDS Micro ATX LGA1150
Sapphire Radeon R9 280X 3GB Dual-X
Unfortunately the location of the front panel connectors on this mobo mean that this gfx card doesn't fit when you assemble everything.
That's a terrible design for a motherboard to have the front panel connectors being blocked by just a graphics card.
There are a few alternatives to returning the motherboard but they would involve removing the power switch pins from the connector and somehow rigging them up to the front panel connector pins (that's the crucial one you need, the power connector).
I'll ensure that the H81M-HDS is removed from all the recommendations. I apologies for the oversight and your hassle of having to rebuild.
Here's an album of pics: http://imgur.com/a/difnm
Bit tricky getting the right angle. I can take the mobo out of the case and take some more if you want.
Yes I tried fitting the connectors first and ensuring the wires were pushed over to the side but the card was obviously being blocked. The card fits in fine without the connectors in place.
I've ordered another motherboard which should be fine so I'll see if I can return the H81M-HDS.