I have the following 2 drives. When I run a disk performance benchmark on them they seem to perform as expected. Both drives are approximately 3 to 4 years old.
500 gig - WDC WD5001AALS-00E3A0
640 gig - WDC WD6401AALS-00L382
A couple of days ago I installed another drive that was salvaged out of one of our servers. It seems to run without a problem but when I run the same benchmarking programs I'm only getting about 60% of the performance that I get from the other 2. I know the manufacture date on this one is about 2-3 years older but I didn't think (or know) that might make a difference. I did research this model and is appears to be an "Enterprise" clase drive. Regardless I'm keeping the drive.
160 gig - WDC WD1600YS-01SB1
Do my observations sound correct? Would this 3rd drive actually transfer slower? From what I can tell these 3 drives are all spec'd the same.