missing ram after case swap

Hi, I was just wondering if it is unusual to somehow damage a ram stick just by blowing dust off it. I did a case swap and had 1024mb of ram using two 512 sticks and never even touched them and after i swapped all the components over to the new case on bootup it's only counting 512 now and XP is only reporting 512mb. The old case was full of dust so I'm wondering if blowing out the dust damaged one of the ram sticks.I tried reseating them but that didn't help. I guess I need to open up the case again and test the ram sticks one at a time and see if one of them is bad to make sure it's not the motherboard. I tried to be really careful but I guess I wasn't careful enough.

 

Good news. I isolated the bad memory module and it has a lifetime warranty from Kingston. As soon as I get an RMA I can return it for a replacement.