My computer uses PC2700 (DDR333). Can I use PC3200 (DDR400)?
DDR memory was designed to be backward compatible so generally speaking, you can safely add faster memory to your computer. For example, you can install a PC3200 DDR module in a computer that calls for PC2700 DDR. However, keep in mind that faster memory will not necessarily make your system faster. You can't speed up your computer by adding faster memory if other components in your computer (your processor or other memory modules) operate at a slower speed.
The right memory for your computer is the kind of memory it was designed to take. Check your system manual or look up your system in the Crucial Memory Advisor to find the memory guaranteed to be 100 percent compatible or your money back.
RESEARCHUT -- Basic RAM Information