Symptoms
- Fans spin up and stay on but screen never lights up
- No display even after waiting several minutes
- External monitor also shows nothing when connected
- Caps Lock or other keyboard lights respond normally
Likely causes
- CommonDisplay isn't receiving a signal due to a graphics driver or hardware faultThe system may be booting fine internally while the screen output fails.
- CommonRAM not properly seated (if user-accessible)A loose memory module can prevent the system from completing boot far enough to show video.
- PossibleFailed backlight or screen inverter, leaving the screen dark but functionalShining a flashlight closely at the screen can reveal a very dim image if this is the cause.
- PossibleExternal monitor also showing nothing points to a motherboard/GPU issue rather than just the screenThis helps distinguish a screen problem from a deeper hardware fault.
- PossibleFailed boot due to corrupted firmware or storageFans can run at a fixed startup speed even if the boot process is stuck.
What to do
- Shine a flashlight very close to the screen at an angle to check for a faint image, which points to a backlight failure rather than no video at all.
- Connect an external monitor via HDMI or USB-C to see if video appears there instead.
- Hold the power button for 15–30 seconds to force a shutdown, then power on again.
- If you're comfortable and it's user-accessible, reseat RAM modules per the manufacturer's instructions.
- Disconnect all external devices and try booting with nothing else attached.
- Listen for a specific pattern of beeps, which some laptops use to indicate a hardware fault code.
Tools and parts
- Flashlight
- External monitor with appropriate cable
When to call a pro
If an external monitor also shows nothing and reseating memory doesn't help, this likely needs a technician to diagnose a motherboard, GPU, or display cable fault.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.