ATI Display driver not detected! X1950Pro

I've installed Vista Ultimate (64) in my new system:

Asus P5B, E6600, 2*1 GB Team Elite (800), Shapphire RADEON X1950Pro
256Mb GDDR3 (Pci-e)

My board is "Vista Premium Ready". I tryed to install the motherboard
CD drivers and an error occur (something about digital signatures and
dll's..). Then, i tryed to install the graphics board drivers CD, but
vista told me I had to be in administrator mode (OS was fresh, no
accounts or passwords configured) to do that.

I went to ATI's site, downloaded the recent drivers (catalyst 7.4), and
installed them. The system detected the graphics board, i'm able to run
a game (Lock On, in highest definition) and it seemed ok. But windows is
not running the AERO feature! Then I got the Shappire drivers (same
catalyst 7.4), and the problem still exists.

"No ATI graphics driver installed, or the ATI driver is not functioning
properly. Please install the ATI driver appropriate for your ATI
hardware"

"An ATI display driver is no currently detected on your system"

These quotes are the sympthom of the problem, and the second one
appeared when finishing the ATI drivers installation.

I went also to Asus support website and downloaded all the Vista
content to my motherboard. But i don't know how to use those files
(zip's with folders and subfolders, some without setup file).

Is this problem related to motherboard drivers, graphic board
drivers?..

Remember that Windows Aero is not working.

Thank you
Diogo


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diofil