If the VGA light on the motherboard is ON, with no display, but GPU works, there may be an issue with your graphics card. Use these fixes to troubleshoot and fix this problem.

If you see a red CPU light on the Motherboard with no display, you will have to take a look at the BIOS, CMOS, etc. Full details here.

But depending on your motherboard, a red light can mean all sorts of things. Let's see if we can figure it out. Asus Check the manual. Almost every manufacturer uses a different layout and design ...