Need help identifying PC memory (PICS- BW WARNING)

[DRR]

Trying to upgrade the RAM in my wife's Sony Vaio VGN-S260. There are two banks, one has 512 and the other is free. Great, I thought, double the RAM for not too much coin.

I looked up what type of memory it takes and I ordered from OWC. It came today, and it's too big. (Yes, I ordered an SO-DIMM for a notebook.)

So I double checked the specs online, and my OWC order, and from what I can tell, it should fit. But it clearly doesn't. So I need a little help.

Here are pics of the memory and the computer:




Here is the dealram.com page whose memory identifier told me what type to buy:
http://dealnews.com/memory/prices/system...512MB.html

And kingston.com agrees. So I bought it but it clearly doesn't fit.

Where did I go wrong??