A few weeks ago, we received lightening damage to a NIC in one of our servers. I replaced the NIC and it worked fine for 2 weeks. Now, that server has taken to dropping offline during the nightly backups. The backup runs completely through, untilit has to backup a drive on the other server. Sometimes it completes and then drops offline, while other times it drops offline during the backup. A System 53 Error is showing up in the Event Log. I have installed the most up to date drives for the NIC, and the diagnostics provided by the vendor say the NIC is functioning fine. We are running NT4 SP5. Any suggestions?