When I press the power button on my desktop, it turns on, the fans immediately ramp up to maximum speed, and all the LEDs light up. However, there is no display or boot process, and neither my keyboard nor mouse receives power when connected to the case or motherboard. I'm not seeing any diagnostic codes or motherboard warning lights. What should I check to figure out which component is preventing it from starting?
3 Answers
This sounds like the system is failing POST, meaning it isn’t getting far enough to initialize the hardware. Check whether the motherboard has any diagnostic LEDs or a two-digit error display. If it has a small motherboard speaker connected, listen for beep codes, since those can point to memory, graphics, CPU, or other hardware problems.
It’s too early to conclude that the whole PC is dead. The symptoms could come from loose power connections, incorrectly seated RAM, the graphics card, the power supply, the motherboard, or the CPU. Testing with the minimum components and trying each RAM stick individually is a better way to narrow it down.
Start with a minimal-hardware test. Shut the PC down, unplug it, and disconnect unnecessary drives, USB devices, and expansion cards. Leave only the CPU, one stick of RAM, and the graphics card if the CPU has no integrated graphics. Reseat the RAM and power connectors, then try starting it again. If it still won’t reach the BIOS, a motherboard speaker can provide useful beep codes.
I don’t see any diagnostic lights or codes on the motherboard, and I’m not sure it has a speaker connected.