Unfortunately the PC only has one PCI slot so I cant try it in another slot, the card itself works fine as I tested it in another system. I havew tried taking it out and reseating it and it hasnt solved the problem.
I also disabled the onboard card in the BIOS and tried uninstalling the Delta drivers and installing the ones that you reccomend and the situation is still the same. I cant change the IRQ assignments on the system for some reason, I suspect its a BIOS setting but cannot find an option for PnP OS or similar.
Anything else you suggest.