Slow Site Performance due to CPU 'throttling'?

[Single Dad]

Greetings everyone,

I'm pretty sure this is not a StudioPress issue, but since all of my sites (5) are running WP 3.3.1 and Genesis 1.8 I thought this may be an ok place to start at least.

My sites' performance has TANKED recently and the server logs/dashboard is pointing to CPU throttling due to 'fcgiphp5' process. Performance is the worst in the morning from about 8am - 12pm then gets better and nearly goes to 0 during the late afternoon/overnight hours (all times EDT).

I've disabled the majority of my plugins, but not quite all (Genesis plugins are left running). Since disabling plugins, performance has creeped further down rather than improving. There are still a few more plugins to try but I was hoping someone else had a suggestion.

Any info is appreciated!

Daniel

Attached screen shot of throttling trend was taken at around 10:30am