[sanddrag]

The question is still, do you have the 5570Z, or just the straight 5570? (indicated on the badge near the lower right of the spacebar)

EDIT: Sorry, I need to learn how to read. You did state it was the Z. In that case, 2 gigs max. There's your problem. I'd return those for a pair of 1 gig sticks, or just toss one 2 gig stick in there, and save the other for another system.