I opened my DSR7000 to try to use the zipper upgrade on it. I didn't actually get any further than removing the hard drive and something came up. I put the drive back in and now when I turn it on it doesn't even begin to try to boot. The fan runs, but it just sits there. There is snow on my TV screen and when the video cable is plugged into the TV the snow "skips" if that makes any sense. Any idea what I should look for? I didn't touch anything inside the Tivo other than the drive.