Augmenting a GPU

I need to know whether it is possible to amp up the power of a video card by allocating some CPU power to processing graphics. Eg if you have a graphics card thats only got 64MB of memory, can you boost it's ability to simulate perhaps a 128MB card?

 

Some video cards have the ability to share some of the computer's system memory. For example: if the video card has 256mb RAM, and you have 1gb of system RAM, the card would allocate 256mb from your system RAM and add it to the 256mb it already has, and you'd have 512mb of video RAM, and 768mb of system RAM. These cards are usually called "TurboCache" or "HyperMemory" or something like that. The amount of system RAM the use depends on how much is available. If you only have 512mb system memory, the card would use only 128mb.... I don't think you can do this with a normal video card, nor can you reserve some CPU computing power exclusively for use by the video card.