[Techtalk] Unknown computer error

[R. Daneel Olivaw]

Hi David,
>
> ata 3.00: status { DRDY ERR }
> ata 3.00: error { UNC }
> ata 3.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x0
> ata 3.00: BMDMA stat 0x65
> ata 3.00: failed commadn: READ DMA EXT
> ata 3.00: cmd 25/00:08:68:35:55/00:00:30:00:00/e0 tag 0 dma 4096 in
>           res 51/40:04:6c:35:55/40:00:30:00:00/00 Emask 0x9 (media
> error)
> 

Your symptoms and this final output confirms: your drive is almost dead.

I'd give spinrite a try in order to clone the disk to a new one without
loosing too much data (non-free, but saved several drives for me in the
past).
Else, dd_rescue can help copying the readable blocks off to another device.

R. Daneel Olivaw,
The Human Robot Inside.