For home use, I'd say start with what you have. You can always upgrade later. Power consumption is the biggest thing. For an always-on home server, you want so

For home use, I'd say start with what you have. You can always upgrade later. Power consumption is the biggest thing. For an always-on home server, you want something that sips as little power as possible. (Some of the Intel Avoton CPUs have a 17W TDP, compared to an i7 which can have a TDP anywhere between 65-150W.) Outside that, the only other issue is going to be lack of ECC RAM. Whether that's needed for a home server is debatable. Many folks can get by fine without it. Oh, and lack of lights-out management utilities. Which is convenient, especially in headless setups... but hardly required when the server is a few feet away.