Symptoms
- Device Manager shows no graphics card or a generic display adapter
- Monitor works when connected to the motherboard but not the GPU
- No signal at all when the monitor is on the GPU's output
- GPU fans spin but the system boots using onboard graphics instead
Likely causes
- CommonMonitor cable plugged into the motherboard instead of the GPUIf a GPU is installed, video should come from its ports, not the motherboard's.
- CommonGraphics card not fully seated in the PCIe slotA card that isn't clicked in completely won't be recognized.
- CommonGPU power cables not connectedModern cards need one or more supplementary power connectors beyond slot power.
- PossibleCorrupted or conflicting graphics driverA driver issue can prevent Windows from recognizing an otherwise working card.
- PossibleFaulty PCIe slot or graphics cardTesting in a different slot or system isolates this.
What to do
- Confirm the monitor cable is connected to the graphics card's ports, not the motherboard.
- Power down, reseat the graphics card fully into its PCIe slot until it clicks.
- Check that all required power cables are connected to the card, matching the number the card needs.
- In Device Manager, look for the card listed with a warning icon and reinstall or update its driver.
- Try the card in a different PCIe slot if the motherboard has more than one x16 slot.
- Test the card in a different computer, or test a different card in this one, to isolate the fault.
Tools and parts
- Phillips screwdriver
When to call a pro
If the card isn't detected in any slot or system, it likely needs professional testing or replacement.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.