Comment 119 for bug 550559

I'm also seeing "failed command: WRITE FPDMA QUEUED" using a GA 990FXA-UD7 board with Crucial m4 SSDs connected to the Southbridge SATA controller (ATI SB950) on oneiric . Sometimes this error would crash the machine (the RAID5 module actually), sometimes it will just reset the SATA link and keep going.

A workaround that solves the issue for me is to go to the BIOS and disable "SATA3.0 Mode" for the southbridge SATA. This reduces the SATA link speed to 3Gbps, although Linux still reports 6Gpbs in the kernel log.

I'm using a SATA drive bay from Thermaltake. Maybe the additional connectors in there degrade the SATA link in a way that makes SATA3 unreliable. This is just speculation, I didn't test it when the drives are directly connected to the mainboard.