geolocation - what kind of code google use for detecting real ip while I'm using putty as a sock proxy? -

For some reason I'm using as socks putty proxy and hide my real IP server in 99% sites But there is an interesting issue in Google websites, Google can not recognize my real IP but can detect my actual location. I'm wondering what type of code Google is using to locate the actual location.

is concerned.

Google your IP You see, regardless of Use cookies for