Power problems on Dell 755

1. Check Power Supply Connections:
   • Ensure that all power supply cables are properly connected to the motherboard, CPU, GPU (if applicable), and other components.
   • Verify that the power supply switch (if present) is turned on.
2. Inspect the Power Supply:
   • Make sure the power supply is correctly rated for your computer's power requirements.
   • Check for any visible damage or burnt smells coming from the power supply.
3. Test the Power Supply:
   • Use a power supply tester to check if the power supply is providing the correct voltages.
   • Alternatively, if you have access to another working power supply, you could temporarily swap it in to see if the problem persists.
4. Check for Hardware Issues:
   • Disconnect all peripherals (external hard drives, printers, etc.) and remove any non-essential internal components (extra RAM sticks, additional drives, etc.) to see if the computer starts with a minimal configuration.
   • Reseat the RAM and any expansion cards (GPU, network card, etc.) to ensure they are properly connected.
5. Inspect the Motherboard:
   • Look for any signs of damage such as burnt components, bulging capacitors, or bent pins.
   • Reset the CMOS by removing the motherboard battery for a few minutes or using the CMOS jumper (refer to your motherboard's manual for instructions).
6. Listen for Beep Codes:
   • If your motherboard has a speaker, listen for any beep codes when attempting to start the computer. These can provide clues about what is wrong (refer to your motherboard's manual for beep code meanings).
7. Monitor Power Save Mode:
   • Ensure that the monitor is correctly connected to the computer and receiving a signal. Try using a different monitor or cable if possible.
   • Check the monitor settings to ensure it is not stuck in Power Save Mode.

If after these steps the problem persists, it might be helpful to consult the documentation for your specific computer model or motherboard, as the blinking amber light could have a specific diagnostic meaning.

If you're not comfortable performing these steps, or if the problem remains unresolved, it might be best to consult a professional technician to avoid causing further damage.