667mhz RAM in 533 MB

[ecpike]

The specs on my MB call for a 533MHz RAM and I already have a 1GB module in there. I wanted to upgrade and add a 2GB module in the open slot but only found a 667MHz module at the store where I have a gift card. Would it cause any problems if I put the new module in with the old, or will it just not perform at its full function?
Thanks!

 

[Zorg]

It should just fall back to 533.