The Matroska Media container is a very popular, open standard Multimedia container which is usually found as .MKV files. It is a very popular format in enthusiast circles and can be played directly in VLC or Windows Media Player with suitable codecs installed.
We played our 1080P MKV movie using the latest version of VLC Media Player and measured the CPU usage with the Performance Monitor built into Windows.
Again we see impressive improvements in real world performance when the system was overclocked.