I am also planning on upgrading to a core i7 920 system very soon. Actually I'm just waiting on the new EVGA classified mobo to be released.

Now I know the core i7's dump more heat and im concerned from my tempatures currently that the current radiator will not be enough.

I have two ideas for what to do with another radiator.

1st: grab a second MCR320 radiator and mount it under my current radiator on the top of the case with 3 additional fans.
What I would do also is have the hotter liquid go to the top most radiator first and then to the second one, but I do not think this will work to well as heat from one radiator is still going across the other.

2nd: I could add a 120.1 radiator mounted inside the case on the back pushing air through the back and out of the case. The problem with this is the back fan on my case is a 160mm I believe, so it might be more difficult to mount.

One thing I do not want to do though is add a second loop. Adding to my current loop is fine just don't want a second one.

Also I would like to keep all WC components inside the case.

If anyone else has any other ideas please post them. Thanks