Google has released Chrome 45 for desktop, which is now available to download on PC, Mac, and Linux. The biggest change in this update is improved RAM management, which reduces the memory usage of idle tabs in the background.
Chrome can now check on tabs in the background and can tell if there is no activity on them for a while. It will then aggressively clear unused memory to reduce the memory footprint of those tabs. Google claims it can free up about 10% memory on an average and as much as a quarter for sites like Gmail.