WD HDD Loud as Women in Cat Fight!

[aphrodit3]

I realize this post may be off topic or posted in the wrong section... please bear with me...any help offered would be greatly appreciated.

I recently rebuilt my PC from an HP to the following...the only constant here is the tower, everything else is changed.

My MoBo is Gigabyte - MA785GM-US2H
My processor is a 2.6 Ghz AMD Phenom II x3 710 (literally 3 cpus in one)
My RAM is 3Gigs.

I've just installed a WD Caviar (blue box) 500Gb SE16 7200 RPM 16MB cache HDD...

The problem is...a lot of good things have been said about this HDD... that it is as quiet as a church mouse and so powerful...yada yada yada..

The only reason I purchased this HDD is because the previous HDD I was using... was loud as anything...and would freeze on me..

Well guess what... I feel and see no difference whatsoever...
I tried Win 7 and reverted back to XP thinking perhaps the OS was the problem... this WD HDD is as loud as you can pick em... and even though task manager tells me the cpu is at 2% capacity... some programs.. firefox, Dreamweaver etc... hang for a moment or two (program not responding)...

Any advice? Did I buy a lemon (HDD) here... do I send it back?
Any recommendations?

Pretty please...I'm getting desperate.

[Cobracon]

If the HDD is making a grinding noise and you can feel a distinct vibration when placing a hand on it, it's safe to say failure is right around the corner. Back up any files you want to keep and contact the supplier or manufacturer for an RMA #.