How to figure out what is wrong with my Western Digital Hard Drive. Where do I start?

My computer is less than a month old.  I have a SSD drive with my Windows Operating System on it, and I have two Western Digital Caviar Black 2TB 3.5" 7200RPM Internal Hard Drives (WD2002FAEX) configured in a Raid1 to store my documents and media.

Everything worked great for the first few weeks but now I have a problem.  The Raid1 has suddenly become VERY slow.  It takes almost a minute to open a folder and duplicating a 100mb file can much longer than that.  It is only about 25% full and is not fragmented.

-I ran windows Check disk on it and it didn’t turn up any problems.

-I downloaded Western Digital diagnostic tools but it will not work because my raid is listed as a “logical drive”.

-I looked in my BIOS and Raid Utility and everything looked ok to my inexperienced eye. 

I am a novice computer user. I do not know where to go next. Please help.

I’d like to add that anything running from my SSD runs quickly with no problems, so I am pretty sure the problem must be with my Hard drives.

I’ll also add that if I open a filder it can take several minutes but if I go back and try to open that same folder again later it will open fast but still open all the other folders slow…

GSmartControl should be able to see your individual drives behind a RAID controller.