Ich habe auf der asus-homepage die lösung deines probs gefunden. Der Lüfter lässt sich über das bios regeln.
Siehe link:
http://support.asus.com/faq/faq.aspx?SLanguage=en-us
Der direkte link wird nicht angezeigt, deshalb habe ich das ganze einmal hier reinkopiert.
Question When I use a fanless or water-cooling setup for CPU, the screen will display a warning during POST. Why?
http://support.asus.com/images/Spacer.gif Answer When A8N-SLI Series motherboard has detected CPU Fan failure or running at a low speed, it will give you a warning to protect your CPU from overheating. If you are using a fanless or water-cooling method for CPU, you can enter BIOS and go to Power -> Hardware Monitor and set CPU Fan Speed warning to "Disabled". If your fan is running at a low speed with high efficiency, you can also set the lowest limit to 800 RPM to avoid the warning.