The driver detected a controller error on \Device\Harddisk1\DR1

My Studio 1558 would only boot up one in three times so I looked at the Windows 7 error logs and found the ERROR: Event ID 11, The driver detected a controller error on \Device\Harddisk1\DR1 appearing every hour or so.

I restored the factory image to rule out a driver corruption problem and now it boots up all the time but the error still appears.

I presume this means I have an intermittent hardware failure in the controller of the SATA drive.

My question is do I simply replace the hard drive (seagate ST9640320AS) or is their a seperate IC controller on the motherboard that is playing up?

Please advise.

Kind Regards
Thymus