I am replacing a failing WD Black 2tb drive. The drive has only music and photos on it. As I copy folders from this drive to a WD Black 1tb back up drive I'm seeing avg transfer speeds of 3-4.5 MB/Second. Sometimes transfer speed starts out around 7 MB/Second, but if it's a large file the transfer speed drops to 2-3 MB/Second. Is this normal? Is it because the drive has bad sectors?
MOB Gigabyte GA-X58A-UD3R
12g ram
WD Black Velociraptor 300gb
2 Samsung F3's Raid 0
2 Samsung F3's Raid 0
WD Black 2tb
WD Black 1tb
Thanks for the help.