Dual monitor problems

I Belive i'm having an unusual dual monitor problem

First my specs!
Graphics card : Advanced Micro Devices [AMD] nee ATI Turks [Radeon HD 6670]
Screens - 24in AOC (Ubuntu in displays calls it a 23in) (cant easily get the model number)
17in Prestigio

The AOC is plugged in via the graphics card.
The Prestigio is plugged in via the integrated graphics

Ubunut Can not see the 17in
However , when i turn off the pc, where the ubunutu logo comes on to shut off the pc, its ONLY on the 17in
Today, when i hit the ctrl + alt + f1 . the AOC when off but the Terminal came up on the 17in

When i hit ctrl + alt + f7 (to switch back) it did , but i can still see the stuff i typed into the terminal ( but i cant type into it)

Apart from this , the screen is blank ( not no signal , just blank)

I really would like some help with this

Thanks
Barry.

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IS this an HP system with dual graphics chips? If so, I don't believe in Linux that you can use BOTH chips at the same time -- with a monitor plugged into the jack being drive by each of the chips.

Thanks for the reply
No it's acer built

The stange this is the switching the display upon shutdown
Any thoughts

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