One of my disks UDMA CRC count goes up every once in awhile, typically while it's under load. It's currently at 13, but everything else in the smart report is fine. Should I replace the disk?

CRC errors indicate connection problems, typically cabling related and not problems with the disk itself.   Also the CRC count never gets reset to zero,   Occasional errors are OK but if they happen more frequently consider replacing the SATA cabling.

14 hours ago, nerv said:

typically while it's under load.

One thing to check to see is that the SATA data cables are NOT tied together to neaten-up the inside of the case.  With unshielded cables, this can cause crosstalk.  (Very few SATA cables are shielded as they are much more expensive!)  Tying them together also increases the problem of moving one cable will loosen another cable from its mating connector.  

 

Another issue is using 'locking' cables with some drives.  You can read about that issue here:   https://support.wdc.com/knowledgebase/answer.aspx?ID=10477

 

 

Thanks folks, will give that a try and see if it helps.

Does disk controller was Marvell solution ?