Separate HDD test using RAID controller

Dbugy

Hello,

I am using Red Hat 2.6.23.1 with RAID 6 controller (card).

(When I use "cat /proc/partitions" I do not see the separate HDDs in the RAID, I see one drive for the RAID itself, as it is considered 1 large drive.)

I used a "dd" check to test my RAID drive speed and found it was a bit slow, so I want to figure out which HDD in the RAID is problematic.

I was wondering I there was a way within Red Hat to test the HDDs separately without destroying the RAID build.

Otherwise is there a 3rd party tool that can help me?

Thanks in advance for any help possible.

P.S.

This is my first post so I don't know exactly what information is needed, please tell me if you need more information in order to help me (and as I am new to Red Hat I would also appreciate explanations on how to get it).