If it's crunching randoms, it will say so in the window when it loads a random block. Crunching randoms means that it is checking blocks that it picked itself, instead of blocks that a Dnet keyserver or PProxy gave to it as "known unchecked" blocks. Typically, some of the randoms end up being ones that have already been checked, so they are duplicates and don't count. Loss is typically in the 30-40% area, I think.