As far as i know mate it has to be EXACTLY the same spec of RAM module your using so id say it not working has something to do with the fact that its 1. not pc2700 and 2. its not 333MHz

Not the answer you were hoping for but i think im correct

Out of interest, apart from the obvious is there any other reason why you didnt match your RAM exactly? maybe they didnt stock pc2700 in 1 gig sticks?