Any normal card reader that can read XD cards will read XD cards in sizes up to 512mb. For 1gb XD cards you are going to have to have a card reader designed to read the 1gb XD cards, because the coding is different on the 1gb and higher XD cards.
My Lexar reader can only read XD cards up to 512mb in size.For my 1gb XD cards, I have to have touse a different reader. I have a newer reader that can read all sizes of XD cards. It does not have even a brand name, It just reads on the top: "20in1Reader-usb 2.0"
Sothe question you should specifically ask is this: "Can this card reader read 1gb XD cards?" it is as simple as that.