Super Cache working, but slow?

A couple problems:

1.) Prior to installing Super Cache, my pages would load in about 2 seconds (for both logged in/out users)

However, after installing Super Cache, pages take much longer – at least 60 to 90 seconds – to load for logged out users. That’s for both the dynamically generated pages and the static ones. For logged in users, the dynamic pages load fast but not the static ones. Is this normal?

2.) If there is a static page already created, logged in users will see it. Otherwise they see the dynamic page.

Am I doing something wrong here? I’ve followed the instructions to the word, and WP_Cache is defined at the top of my wp-config file.

Thanks.