Usually, you can get a freeware hd diag utility from the hd maker's website, like powermax from maxtor and use it on a separate boot disk. But that utility is desinged to work with just that drive most of the time, but they someitmes can be used for different hds.

But if you want to use 1 utility for all hd's then I found Ontrack to have the right one for you maybe.

http://www.ontrack.com/dataadvisor/