I have been running the XDream on my AMD 1800+ for some months now. It was easy to install (although some mobo's might have a space problem with the clip handle).
Mobo's temp change from =- 64°C to mid to high thirties (running at slow speed). I haven't had the need to run the fan at full speed at all. (Gets VERY hot here in South Africa > 30°C).
Just me sure to use a good thermal paste (Arctic Silver is the best).