I looked up your graphics card which has a very impressive description, so I have to agree that your computer specs are probably not the problem, though I would do a reinstall of the drivers just to make sure all the bases are covered. No matter how powerful your equipment is, if your graphics driver has become corrupt for any reason (usually at no fault of the user) it won't work to its best abilities.
Also, check your graphics card settings to see if there is a way to disable or adjust it's "GPU boost" feature. While NVIDIA is one of the best (if not the best) graphics card designer on the market, it does have a history of introducing new features that promise great things but deliver less than satisfactory results. Here is the link to the "Features" section of the site for your card:
http://www.geforce.com/hardware/desk...x-680/features.
So I would look into this feature and the other settings for your graphics card to see if there is a way to fix this problem. It would at least rule out or confirm the hardware end of your troubleshooting of this problem. I'm voting it would rule it out.
Beyond that, I agree that checking to see if other addons are causing a lag problem with Carbonite is a good idea and may help you solve the issue. If you raid a lot with two instances of WoW on, there may be some addons you use that are contributing to this problem. If you find that to be the case, hopefully they will have an option for enabling/disabling them in game that can be set up with a macro.
You may also find completely removing Carbonite and reinstalling it may be the fix your looking for, especially if you have only pasted or installed new versions over the previous ones. With the latest update, it would be a good time to do this.
Good luck, I hope you find the problem or the latest update or a future update of Carbonite will eliminate this problem.
(note: I envy your system.)
