I have a Compaq Presario 2100 and am looking to upgrade its memory. I was looking up what it can take it supposedly 512MB PC2100 DDR266 SODIMMS. Best Buy has a deal on this 512MB PC4200 DDR2 SoDIMM. I want to get the max amount of memory in it and I'm wondering if I'll be able to use it. Thanks for the help.