We have an HP ML350 G5 server, with an HP E200i Sata RAID controller. We have a RAID 5 Array with 3 1TB drives. For the past year or so about once per month one of the drives--usually drive 1, occasionally drive 2 will drop from the aray with no indication of failure. When looking at the server all of the LED's on the drive will simply be off. The server, itself appears to freeze up--or maybe more accurately just comes to a slow crawl. Generally to fix the problem we can simply remove the drive and replace it. The array then finds the drive and the machine conitinues most times not even rebuilding the array--as if nothing happened. We have replaced the controller, and several drives and the problem always seems to come back at some point. We have contacted HP support which has for the most part not been very helpful--suggesting various firmware updates which have helped some, but really have not fully resolved the problem, and really for the most part these folks feel that because we can resolve the problem by resetting the drive, there is no problem. Of course to me it is most annoying to have to come in on my days off, late at night, or at the crack of dawn to reset a drive. We have had several servers that have run 24/7 for years on end witout having a single issue. Has anyone seen this type of behavior before and have any idea how to correct this?