Hi Peggy,

No, an older motherboard probably cannot use the PCI E2.

For others following this thread, please be advised that the amount of RAM a video card uses has a high priority on Windows memory usage. In non-geek-terms, if you purchase a video card with 1 GB of RAM on it, that is going to consume 1GB of the 2 to possibly 3 GB ram your windows is capable of allocating for all your current windows processes, and everything else will be forced into your hard disk swap space.  

Basically, for Windows XP users, a video card with 512 MB of video ram on it hits the "sweet spot" in terms of maximum computer efficiency. More video ram than 512 MB  forces windows to start making hard disk swaps, causes more motherboard throughput processing and begins to degrade overall processing speed.

For Vista users, it all becomes more problematic - that is, depends upon the particulars of your hardware, but more video ram will not impede much.