I have managed to find the settings in the BIOS.
It was within Boot Options - didn't think of looking there!
There is a greyed out setting: "On Board VGA" which is set to Auto, so I am guessing that is all OK and it should recognise it -maybe when the card is installed, it ungreys and allows it to be manually set?
Thanks for everyone's help
I will let you know how I get on, just need eBuyer to confirm whether it has a DVI-VGA connector included!