I have installed SL 5.1 many times! The file system can be corrupted easily! I don't know whether it is RedHat Linux's weakness. Here are my experiences: Case 1. The system might stop here at boot time: RedHat Nash 5.1.19....... After rebooting, it might boot normally or the system went corrupted and no more boot again! Case 2. I installed 2 SATA harddisks as mirror pair on a SiI SATA software RAID card. Installation is successful but after several days' operation, the system could not read the RAID pair. Formatting was needed. Case 3. After several days' downloading of a movie file through Ktorrent, the file system went corrupted again! Formatting harddisk required. I heard that downloading BT file hurts hard disk very much. However, Case 1 and Case 2 do not have any relationship with BT task. Any technique or trick to avoid this?