Western Digital disk WD5000AAKS-75v0a0 vs ones without a dash

Question

In one of my computers I have 500GB x 2 WD5000AAKS-75v0a0 in RAID-1 configuration. I was hoping to keep an identical drive on hand as a spare and started looking at prices. First I found this exact WD5000AAKS-75v0a0 drive only on a few sites, and they were fairly spendy (~USD200 or more). Tigerdirect sells WD5000AAKS (unspecified extension such as 75v0a0, so to say) for around USD40 -

1. Would you know the difference between WD5000AAKS and WD5000AAKS-75v0a0 or disks with other extensions such as WD5000AAKS-22a7b0? I contacted WD by phone and the rep didn't have an answer or spec sheet for 75v0a0 or 22a7b0. I use 22a7b0 disk just for comparison.
2. In your experience, can I just buy any WD5000AAKS 500G disk to replace a faulty disk in the RAID array?

Thank you.

Answer 1

I found the answer in a PDF file. WD5000AAKS is split into WD 5000 A A K and S, which indicates company initials (WD), capacity (500G), units and form factor (GB and 3.5 inch), business brand (Desktop/WD Caviar), rpm (7.2K/16MB cache) and interface (SATA 22 pin) respectively.

The suffix 75v0a0 or 22a7b0 are for WD's internal use. 75 indicates OEM information and indicates the disk went to Dell. V0 and a0 perhaps indicate the type of ball bearing and firmware, but I am not sure.

There is an informative discussion on forums.storagereview.com/index.php/topic/22131-western-digital-hard-drives-deciphering-the-extended-model-%23/

I am concluding that WD5000AAKS disks are interchangeable, and can indeed be found for $40-50.