Asymmetric versus interleaved memory

I have something wrong with my mobo - 4 identical sticks ram BUT the 4th slot won't let any stick seat (Asus P5GD1).

So, the question is, is it better to run 2 sticks as interleaved OR 3 sticks as asymmetric?

edit: Samsung PC3200 DDR400 512 each)

 

As a follow-up to my original post: I am told the interleaved was the better option.

Also, I was finally able to insert the ram into slot 4; it was extremely hard to press in (we are talking I thot the board would break here).

Anyway - carry on.