lcd TV: panels or driver limit capabilities?
An LCD panel is comprised of a glass substrate with transistors printed on it along with Si based driver chips that are bonded to the glass to driver the columns and rows.

So what you are calling drivers and driver boards are NOT really the drivers. You are looking at what is know as the controller, and that has no limits on the speed.  For the most part, the glass panel is matched to a given driver and the interconnect is through ACF (Anisotropic Conductive film).  Essentially, even if you could take the drivers off and replace them, it is unlikely you could find a replacement.

Aside from the possibility of doing it, and getting to the meat of your question. The panel is the limiting factor, in fact the transistor that charge and discharge the pixels are the limiting factor. Most LCD's are built with amorphous Silicon which has poor electron mobility, there are newer panels made from IGZO, but these have yet to make main stream volume production.