Freenas freezing - ata5: FAILURE - out of memory in start

Good afternoon everyone!

I have problems in my FreeNAS server (FreeNAS-9.2.1.5-RELEASE-x64).

Every day he crashes and repeatedly displays the following warning:

ata5: FAILURE - out of memory in start

After that I can not access the server. I need to reset the server to regain access.

Any suggestions of what can be causing this?

Server configuration:

DellPowerEdge T300
Proc: 1x Intel Xeon X3323 @ 2,50GHz
RAM: 4GBDDR2 ECC
Storage: 5X Seagate SATA 1TB Raid-Z (~3,6TB)
Network: Broadcom...

Freenas freezing - ata5: FAILURE - out of memory in start