If you're starting with the mobo, you'd have to make sure it supports your current memory, eg SDRAM. Many new mobos are moving to DDR RAM, such as 2100 or 2700. If you're upgrading slowly, I'd go for a bundled package with mobo, processor and RAM all supplied together. This way, they're optimised for each other. Consequently, it might be better to save up your cash a bit longer and get a bundle. But I know how cash burns a hole in your pocket.