ASRock Z170 Pro4S Ethernet blinking yellow

I've recently built a new PC with a ASRock Z170 Pro4S motherboard. The installation went fine, except that the ethernet seems to be really sluggish compared to my other machines.

grandmasterj7 wrote: I've recently built a new PC with a ASRock Z170 Pro4S motherboard. The installation went fine, except that the ethernet seems to be really sluggish compared to my other machines. The lights on the ethernet port show a solid orange and a blinking yellow light? I might be wrong, but should the light be green instead? I have tried changing cables with my other machines, but it seems to make no difference. The ASRock board stills shows a blinking yellow light, while the other show a solid green. Is it a possible board defect? Is there some way to check?

First, your board has the standard Intel 219V networking chip built into the Z170 chipset. The following is from your board's manual about the two LEDs used with the RJ45 network jack. This is the same for all Intel and other networking chips used with ASRock boards:



Sorry to say, but your description of the behavior of the LEDs does not make sense. Are you sure you are looking at them correctly? The orange or green Speed LED should not be blinking.

To check the speed of the network connection, have you opened the Windows Network and Sharing Center feature, and clicked on the Connections entry, which usually is Ethernet?

That connection speed is not the actual data download speed, which can be affected by many things. First we need to verify your network LEDs, and the network connection speed you have in Windows.