Stop rendering when no pixels found in a particular composition

[Avinash Ramanath]

Hi,
Am making a 6 minute composition and designing a ticker. I have to pre-comp the text layer as i have to make the text layer dynamic. The ticker width varies according to the number of characters.

Can after effects stop rendering the TGA sequence as soon as the ticker has scrolled out of the screen? or in other words can after effects stop rendering when no pixels are found in a particular comp?

Please help me.