CCGrid3DAction drop the framerate

Hi,
My framerate dropped to 25 from 60 after I run CCGrid3DAction.

I saw some forum suggested i change my projection method to 3d from the default with 2d. But I am afraid it will cause other error.

Any suggestion is much appreciated.

Regards;

What version of Cocos2d-x? Are you seeing the same frame rate drop in TestCpp?

I used cocos2d-x 2.1rc0-x-.2.1.4
If I run it alone(without any other sprite or action), the framerate is 60fps.
But If combined with other action sprites, frame drop dramatically.

Any suggestion?

Thanks;