Can't install/use a 4th HDD

[exomail]

Hello, I bought a new HDD, so now when I've installed it my other drive doesn't work.

Specs:
Motherboard - GA-Z68X-UD3-B3
Disk X - WDC WD15EARS-00MVWB0 (Western Digital)
Disk Y - ST2000DL003-9VT166 (Seagate)
Disk Z - Hitachi HDS5C3020ALA

Today I bought Disk V - ST2000DM001-9YN164 (Seagate)

Now when I installed my new Disk V I started having problems when copying from Disk X, I have no problems copying from Y & Z, but when I copy from X the process stops after several seconds and I cannot properly access Drive X after, I had to reboot every time.

First, I tried different ways to connect to power cables. DIDN'T HELP.
Then I tried different combinations of SATA cables. DIDN'T HELP.
Then I tried to connect to a different power cable that's connected just to my CD and SSD. DIDN'T HELP.
Then I tried to connect to a different SATA controller. DIDN'T HELP.

I've tried chkdsk numerous times on Drive X, no errors... and obviously there's no problem when I copy from X to Y or Z for example. It's just X vs. V that's showing problems.

I'm out of ideas how to fix it with my limited knowledge. So I need your help. Please don't offer to copy from X -> to Z -> V.

 

[exomail]

Please list system specs... I think you may have a PSU issue. how old is it?

chieftec bps-750c

 

[geofelt]

I think two extra 6gb ports may be implemented via a marvell controller chip. Possibly it is not working properly.
Check the bios to see if there are any settings, and see if you hneed any chipset updates.

In theory, 3gb and 6gb sata cables are compatible. But 6gb cables are supposed to adhere to stricter standards.
If you don't know you have 6gb quality cables, try some, at least on the 6gb ports.