What is the computer used for? What is filling up the logs? If this happend in a short amount of time and the PC is not recieving a heavy traffic load, then there might be something really wrong. I would check it out, there are a few people here that know there sh_t when it come to security. So, look through your log file and see which ones are the biggest. Then look through then and see what is filling them up.
Try logrotate, it should come with Mandrake.