Mac Pro extremely slow. HELP!!!

[elit3nemesis]

Open Disk Utility, show us what options you have.

 

[pastrychef]

1. On the left, highlight the drive you wish to install OS X on. Highlight either Hitachi HDS72101..., WDC WD1001FAL..., or Hitachi HDS72101... (I suggest you not mess with the RAID volume for now. It would just complicate matters.)
2. Once highlighted, press the Erase button on top of that window. Keep in mind that whatever data on the drive you selected will be lost forever.
3. A drop down menu will show up. Click Erase.

4. When done, quit Disk Utility.
5. You will be returned to the screen as you showed in post #23 of this thread. Choose Install OS X and follow the on screen directions.

 

[elit3nemesis]

I was able to get the computer to work on the RAID HD.

When I try to open either one of the Hitachi HD it says this:
Unmounting disk
Couldn't open device
Operation failed...

What does that mean?

Thanks for all the help.

 

[pastrychef]

Not sure but they may be what your RAID array is comprised of.