WD SATA II Suddenly very Slow

[au_windroid]

I just built my PC as follows

Asus Maximus VIII ranger, Core i7 6700k with corsair H80i v2 cooler, Corsair 8+8 GB RAM 2400MHz.

I am using my previous PC WD 2TB caviar blue SATA III + WD 320GB SATA II.

Windows 10 64 bit installed on 2TB.

It was working fine. I was transferring data from SATA II to SATA III. All of a sudden data transfer stopped. I cancelled the transferring and again trying copying the data but it was very slow like 200KB/sec, 1.5MB/sec as shown in windows 10 copying tool. I stopped it again.

I can see the data on this drive. I can go through the folders inside. Folders with pictures take long time because of showing thumbnails.

Is SATA II is backward compatible to SATA III?

Please help me how can I fix it? Your support is required.

thanks

Also windows task manager shows 100% activity time and read/write speed 0KB/0KB

 

[Boogieman_WD]

Hey there, au_windroid.

Sorry to hear about the issues you're experiencing. :\

First I'd recommend that you backup your important data just to be on the safe side.

Yes, the SATA interface is backwards compatible, but that doesn't have anything to do with transferring files between two properly recognized drives in one system. However, the good thing about it is that if you have any other spare SATA ports, you could try the drives with different SATA ports and different cables, to see if the issues still persist (regardless of the drives and the ports being different SATA revisions, e.g. SATA II and SATA III). If nothing changes, I'd recommend that you download DLG (Data Lifeguard) and run both tests (Quick and Extended) on both drives, to see if anything alarming shows up.

Hope that helps. Please let me know how everything goes.
Boogieman_WD