new hard drive issue

[jaado]

I recently upgraded my HD to a SSD. So I formatted my current HD and was trying to use it as an additional drive.
Computer works fine with just the SSD. But when I plug in my old HD (it was partitioned before but I formatted to one single drive), my PC doesn't like it and it keeps on trying to load OS. Not sure how the BIOS or motherboard is configured for it to do this..

I have to disable the port in BIOS for this hard drive for my PC to boot up. (I see the hard drive in BIOS setup but not in Disk Mgmt earlier, now I cannot it even boot with my old HD enabled).

Specs:
Manufacturer's motherboard name: Pegatron M2N78-LA  (Specs here : http://support.hp.com/us-en/document/c01925562)
HP Machine # p6310f


I don't have any knowledge on BIOS or how this works. Can anyone suggest me a solution if there is one? I am attaching screenshots of the BIOS and one error that I don't see anymore.

thanks.

[Aetherhead]

What OS was installed on the old drive and what is installed now on the ssd?

my PC doesn't like it and it keeps on trying to load OS

Do you mean it's trying to load the old OS, or does the computer just hang loading from the ssd?