Consider the following scenario:

• You have a Windows Vista-based computer.
• The computer has both of the following:
  • An AMD 780G Chipset with ATI Radeon HD 3200 integrated graphics processor
  • An ATI Radeon HD 2400 Series graphics card
• You have the ATI Hybrid CrossFireX feature enabled.
• The system enters the Sleep (S1) mode.

In this scenario, you cannot wake the computer by using the mouse or the keyboard.

Consider the following scenario:

• You have a computer that is running Windows Vista Service Pack 1 or Windows Server 2008.
• The computer has an integrated graphics adapter and a discrete graphics adapter.
• When you start the computer, you are using the discrete graphics adapter for the display output.
• You switch the display output from the discrete graphics adapter to the integrated graphics adapter.
• A power event occurs. For example, when your AC power cord is disconnected, the power supply system fails over to a DC power source.

In this scenario, you may receive the following Stop error:

Stop: 0×00000018 (parameter1, parameter2, parameter3, parameter4)
REFERENCE_BY_POINTER

Note: This problem occurs only on computers that have certain hardware installed.

On a Windows Vista-based computer that includes PowerXpress technology, you enable the Windows Aero feature. When you switch from integrated graphics to discrete graphics, the Direct3D (D3D) application stops rendering graphics.

The problem also occurs in the following scenario:

• You have a Windows Vista-based computer that has more than one graphics processing unit (GPU).
• You switch from one GPU to the other GPU.
• You use Device Manager to manually disable the GPU from which you switched.

On a Windows Vista-based computer, assume that you have a graphics card installed that uses system memory to augment dedicated video memory. In this situation, the Windows Aero feature may be disabled when the operating system runs under certain conditions, such as in multi-monitor configurations.

You run the Windows Experience Index (WEI) to measure the capability of the hardware and software configuration on a Windows Vista-based computer. After you do this, the score for 3D business and gaming graphics performance may not accurately represent the actual performance of the gaming graphics. For example, the actual performance of the gaming graphics may be less than you expect, based on the WEI score.

In Windows Vista, the dedicated graphics memory that is reported by the “Performance Information and Tools” item in Control Panel may be less than the actual graphics memory that is available for the primary video card.

The dedicated graphics memory is reported under Graphics in the “View and print details” page of the “Performance Information and Tools” item in Control Panel.