What is the largest Compact Flash memory card you go to work with a Olympus E-20?

Some one gave me the Olympus E-20. Nothing would work until I got a compact flash card for it (some one said that was normal). Now the control panel tells me that there is battery power and a CF card, but nothing else. Nothing in the view finder. It does not take a picture.

One review said it worked with larger CF card (they did no say how big, mine is 4gb) except a Sans Disk card.

How big and what kind of CF cards have you used?