A premium monitor will do your photography much better justice when paired up with a good graphics card. What kind of monitor do you have?
As for graphics card, is there a price range you'd like to stay within?
I'd suggest looking at the ATI FirePro or FireGL workstation cards.
Thanks for your quick response,
Very soon I'll buy either a NEC or EIZO monitor of around 1500 Euro's. Currently my main display is a good CRT Philips which I calibrate regularly.
As for the graphics adapter: I would like to spend no more than 250 Euro's...