Hey there, tnance24!
I'm sorry to hear you encounter such a slow performance with your WD HDD!
However, I'd still recommend you to run the QUICK and EXTENDED tests from
WD's Data LifeGuard Diagnostics for Windows and make sure to check on the SMART data results, not only the health status.
I'd also advise you to perform a full backup of the data you have on the hard drive and make sure you copy it to a different storage drive/device before proceeding with the troubleshooting.
Another thing you might want to try is switching the SATA ports on the mobo or even give a different SATA cable a try. Hopefully, this would improve the transfer rate.
Keep me posted!
SuperSoph_WD