My coputer is a 2001 and has only two 256 memory sticks so I know its slow. My sister stayed with us for a while and hers would back up a dvd in about 20minutes, mine takes about 52 minutes. I'm useing an external HP burner thats new. I've tried shutting down programs not needed to free up memory but the back ups I'm making are skipping and have the digital blocking problem. Could it be my burn speed? Its set to max. I'm useing Sony dvd-r discs 120min, 4.7GB.