2Gb of DDR2 800(pc2 6400) or 3Gb of DDR2 667(pc2 5300)

Upgrading the memory on my laptop, and it comes with 1gb of ddr2 667 memory. I bought OCZ 2GB 200-Pin DDR2 SO-DIMM DDR2 800 (PC2 6400) Notebook Memory - Retail, and wasn't sure whether I wanted the faster 2Gb (replacing the stick) or slower 3Gb (just adding the stick). I now realize that my motherboard might not even utilize the ddr2 800, so did I end up wasting the extra 40$ for better speeds that I can't even use?

Did you check the specs of the laptop to see if it would take DDR2 800, or are you just saying it doesn't feel like a huge performance gain? I'd stick with the DDR2 800.