I moved my computer into a replacement case after the original one was damaged. I connected the motherboard, CPU, graphics card, power cables, and case buttons, then performed a test startup. The fans spin and the lights come on, but there is no video output. The motherboard's indicator lights also stay off. I also reapplied thermal paste to the CPU. The CPU power connector has been checked several times, along with the 24-pin motherboard connector. My power supply does not have the additional 4-pin connector intended for overclocking.
1 Answer
The missing 4-pin overclocking connector usually isn’t required for a normal startup, so that alone shouldn’t prevent a display signal. Since this happened during a case swap, recheck every connection and make sure the motherboard isn’t shorting against an extra case standoff. Test it outside the case on the motherboard box with only the CPU, cooler, one RAM stick, graphics card if needed, and the required power cables. Also verify that the monitor cable is connected to the graphics card rather than the motherboard video port.
I’ve checked the 24-pin and CPU power connectors several times. The extra 4-pin is only for overclocking, and my power supply doesn’t include one.