PowerMac G5 Won't mount a 2nd HDD

[WalnutSpice]

Since I've built my new PC, I haven't been using the G5 much, but I hooked it up in a spot outside my room for everyone else to use and my mom and brother have been using it for internet stuff.
Today I decided to throw it back onto my set up and throw in a second hard drive to clone my PowerBook too, then clone my PowerMac HDD to the PowerBook. I wanted to do this so I could have Leopard on my PowerBook just to see how it runs compared to the Tiger install I have on it currently, and wanted to back the Tiger install up to a second HDD in the G5 so I could clone it back to the PowerBook.

So when I did this, I moved the primary hard drive up to the top (Been plugged in as B, so I changed it to A). Then I put the second HDD in the bottom. I also decided that this time I did it, I would do it right and screw them in place instead of just setting them in there. Which was dumb because now the new one is stuck in there, and refuses to mount. This is the second one though, the first one I put in didn't get stuck, but it didn't mount either. So I have no idea what it is. Just a few months ago I was using this with my 1TB and 500GB WD Blue drives and it was just fine.

 

[Intell]

It refuses to mount is OS X? What model drive is it?

 

[WalnutSpice]

It refuses to mount is OS X? What model drive is it?

500GB Western Digital Blue. I've tried two and neither worked, but just a few weeks ago the both of them worked in here just fine. I tested them with my PC build earlier and Windows 8.1 mounted them just fine. It seems Leopard on my G5 and my Tiger install DVD both do not see them on the G5.

 

[Intell]

Do they not show up at all in Disk Utility? Have you properly set the jumper on them? WD drives often don't show up at all unless you set the jumper on them to force SATA I.

 

[WalnutSpice]

Do they not show up at all in Disk Utility? Have you properly set the jumper on them? WD drives often don't show up at all unless you set the jumper on them to force SATA I.

How does one do that? Are the schematics or whatever for that online?
Also, why it work before w/ out jumpers but not now?

 

[mikiotty]

It should be printed on the disk label, on the top of the disk

 

[WalnutSpice]

It should be printed on the disk label, on the top of the disk

That just tells me the pin layout