Windows 7: Computer believes 2 monitors are connected when only 1 is

I have recently bought a new computer, so I took my SSD and all of my HDD's out of my old PC and put them in the new one, although i decided that i would like to use my old setup to learn how to overclock. (the computer was going to get thrown out so if i destroy it it doesn't really matter) I was given an old 40GB which i planned on installing windows on.
The problem is that I connected my display to the onboard when installing windows as the computer wouldn't boot from anything. (i also reset the bios, removed the graphics card completely and used a bootable USB flash drive to install windows as i didn't know the real cause of the problem) After windows was installed i put the graphcis card back in, but now the computer believes that 2 monitors are connected to the computer when in reality only 1 is.
I've Googled this and found nothing and absolutely nobody i know can work the problem out, please tell me if you need any extra info as I am more than happy to give it to you if it helps you work out my problem.
thank you in advance

Did you turn off the onboard graphics card (in the BIOS)?

I am unable to view any of the startup screens (motherboard screen, mac address screen, bios etc.), the first thing i can see when the computer starts is the windows logo, until then, the screen is just black

Try holding down the "F2" Key (or "Del" key) when you power on or reboot your machine (it may beep annoyingly).

i have done this, i know it can enter the bios, i just cant view it. the computer believes the non existant monitor is the main one, so all the booting stuff would be viewed there instead of on my one.
no matter how often i choose the real monitor as the primary one, the computer still believes that the fake one is the number"1" monitor while the real one is number "2"

a screenshot, i hope this can help you:
i.imgur.com/Nf9nqwk.png

It doesn't.
Is that supposed to be a link?

I entered that file name in imgur.com and it said there were 0 results.

What happens if you:

• Swap the monitor connection to the other video connection on your machine?
• Remove the plugin graphics card?
• Boot into "Safe Mode"?

i didn't post it write, just copy that into the URL, should work (works for me)

i just plugged the graphics card back in(it was disconnected and i was running from onboard) and now it seems to be working perfectly
thank you for your help, even if i don't know what the initial cause for this problem was

The lack of "http://" threw me.

I just tried it (as you suggested) and it works.

The OS must have got confused.

I wasn't much help, since you fixed it yourself.