There is some kind of conflict between WP Super Cache Version 0.9.9.7 and Gravity Forms 1.4.5.
When they are both activated, I get errors in the dashboard feeds - Incoming Links, Plugins and WordPress Blog.
This is the error:
Fatal error: Allowed memory size of 33554432 bytes exhausted (tried to allocate 122880 bytes) in /xxxx/xxxx/xxxx/wp-includes/class-simplepie.php on line 14440