The overclock seems stable. I'm worried about the temperature and voltage to achieve said overclock.
The design of the 600T allows two 120mm fans in the top compartment above the actual case. So I had this:
Hot air exhausted out
Top of case
The only option is to flip the fans around, which I just did. I'll test and update this thread.
Before the flow of air was outside to inside, correct?
Your diagram shows it being set to internal intake and external exhaust.
What configuration are you using right now that you have changed your fans?