Dell Optiplex gx240 hard disk problems.

[Rip_Uk]

A friend has given me a Dell Optiplex gx240 to look at. When I turn the computer on I get the error message: "primary hard disk drive 0 failure".

I have literally looked at everything in my knowledge and still cannot find out why I am getting this error.

I have changed the ribbon and moved the hard drive to a different area of the ribbon.
I have moved the jumper settings to every possible setting.
I have moved the hard drive to a different IDE input on the motherboard.
I have tested another hard drive.
I have attempted to load the Windows XP disc up and it continues through installation and then I get an error message informng me that no hard drive is installed.
I have disabled any other hard drive setting in the bios

But, the hard drive still shows in the bios!

Is there anything I may have missed here? is the motherboard at fault? how do I remove the CMOS battery to reset settings?

 

[Rip_Uk]

I have now replaced the CMOS battery and reset the bios setting and I get the same error. Could the problem be the onboard IDE controller on the motherboard? this would mean a new motherboard that most likely is not worth replacing.