Single or double sided RAM? Does it matter

Question

Hi again,You kindly provided me with somegreat info regarding upgrading my memory for my Asrock K7VM2 Motherboard. Many thanks.Can I ask a further question, does it matter is the memory is single-sided (32Mx8) or double-sided (64Mx64)?My existing 512MB says 32Mx8 but Ive been unable to find this info out on memory Im looking to buy online. I doesnt seem to be listed.Do you think that this memory will be compatible:http://www.ebuyer.com/product/45120/show_product_overviewThanks again for you time.