I’m not sure what that “without Windows 8 being installed” part is supposed to mean.
I purchased a new computer last February, with Windows 8 pre-installed. I then purchased a second hard drive, and installed that. And then I installed opensuse 12.3 on that second hard drive.
If that is what you are asking, yes that can be done.
Your system probably came with UEFI, and you might run into some quirks with that newer firmware, as support is uneven across vendors.