SEO Tip #33: Can the geographic location of a web server affect SEO?
Matt Cutts: Yes it does because we look at the IP address of your web server.
So if your web server is based in Germany we’re more likely to think that it’s useful for German users. That’s not the only country we’re going to return you for and we also look at the TLDs. So we look at .de, .fr, and all those sorts of things.
You can also specify in Google’s Webmaster console and say, “Yes my site, my.com or .net or whatever, is about this specific country. You can even do that for specific parts of your site like de.something.com, or fr.example.com.
So I would absolutely recommend that you use those tools. You know if you find a great deal in a particular country and you really want to stay in that country with your web server, I think it’s fine. But if you are worried about it or you want to experiment, you can certainly try switching the geographic location of your web server, which is essentially changing your IP address, and that might end up helping for various countries. So it’s the sort of thing where I encourage you to experiment.