Upgraded EX470 with a 2TB WD Caviar Black running HP MediaSmart 3.0. Single drive only.

Only use is to back up client computers.

No add-ons of any kind.

All media services (including TwonkyMedia) have been disabled, including streaming. No remote access.

Box is working without issues. But few times each day (outside of backup windows), the disk would randomly but constantly thrashing for about half an hour and then just stopped. Not using any sharing features. I understand that shadow copy may be a cause, but in this case I don't think that this is the case because the thrashing would occur when the system was idling and no new files had been copied over to the build except for those from the nightly backups.

Can someone give me some tips on troubleshooting this?

It has been awhile since I had the 470, but does it come loaded with the McAfee Virus scanner Addin installed?
If so, then it is probably scanning for bugs, if not, I don't know how you would find out, maybe remote desktop in and check Task Manager, see what is chewing on those drives.. I would check services and make sure Twonky is stopped for sure.

Also, I would install the Free addin: Smart
http://www.dojonorthsoftware.net/dl/InstallHomeServerSMARTClassic.zip

It may not tell you why the disc is working so hard, but is a must have imho to keep an eye on that drive.

Good Luck

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