Recently quite a few ASUS motherboard users feed back that every time when computer starts up, it prompts “pcdesigner Fan Error”, and they have to press F1 to continue. These problem motherboards include M2N-MX, M2N-VM, and 945GC etc. The cause of such a failure is mainly owing to motherboard unable to detect the rpm of their CPU fans.
Since a motherboard has a video card fan port, a CPU fan port and a system fan port on it, if the CPU fan’s connectors have not attached to the CPU Fan port, motherboard has no way to perceive its fan speed, so you have to reconnect them. Now most fans are 4-pin connectors, but ports of some CPU Fans only support 3-pin connectors, thus the connector on the most top has to stay out of the port.
If the fan is working in harsh environment, excessive dust would inhabit it leading to the fan moving slowly or being out of order. This problem mostly happens when your motherboard has been used for a period of time. You need to put some transformer oil on the fan after cleaning it.
If your problem is still there after checking all above things, you can try below two methods.
1. Enter BIOS and check the first boot driver, if you have set it as boot from CD-Rom but there is no insert disk in the CD-Rom, warning message would also turn up. At this point you should set the first boot driver as boot from hard disk.
2. Go to BIOS, find CPU Fan Speed, and then change N/A into Disabled or Ignored.