IMac 20" (2006) display brightness down after restart

Hello, i'm having a strange issue with my 20" iMac in the sense that after each restart the screen brightness is pitched all the way down to it's lowest settings. It's not a major problem, but it's still quite annoying.
Anyone else has this? Does anyone have a solution?

My iMac does this every once in a while. Not really sure why.
There are screen brightness buttons on your keyboard. They are the F1 and F2 buttons and can be used to quickly adjust your brightness without opening System Prefs.

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    Even when I swipe to the dashboard the outlines are still there when I know they should not be.
    The shadow of those opened documents are still there hours later after shutting down and restarting my computer.
    What is happening and what shall I do? Thanks in advance.

    Not much to go on in your product info, but maybe this will help: iMac (27-inch): AMD Radeon 6970M Video Card Replacement Program. If not, then it's time to visit an Apple repair station.
    27" i7 iMac (Mid 2011) refurb, OS X Mavericks (10.9.4), ML & SL, G4 450 MP w/Leopard, 9.2.2

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