Don't believe me? Just read this: "... PerfHUD 5.1 Highlights:
- GeForce 8 Series support on Windows Vista and XP (older GPUs are also supported)
- Microsoft Windows Vista support (DirectX 9 and 10)
- New in 5.1! Instrumented driver updated to 163.71
- New in 5.1! Compatibility with Managed and XNA applications ...".
To download this great real-time perfomance analysis tool, just navigate to this page.