Probably a dumb question, but is it possible to upgrade a CPU after installing one the first time? Naturally, the new CPU would be the same company (Intel) and it would be compatible with the motherboard.
You have to be careful with Intel, because not ALL LGA 775 motherboard support Core 2 Duo and not even ALL motherboards support the 9xx presler series CPU. You MUST read the Support CPU list really carefully. There are some boards that say they are Core 2 Duo compatible, but only support ONE of the Core 2 Duo CPUs.