Before referring to our RMA service, please, try this troubleshooting guide to make sure that there’s real problem with PSU and not with some other PC component.


Symptom 1: I have plugged the Power Supply into the wall outlet and it doesn't work.

Possible solution 1: The Power Supply has to be installed in a PC or connected to a Power Supply Tester. Another option is the Jump Start (also known as Paper Clip test). PSU can't turn on by itself.


Symptom 2: My PSU is properly installed in a PC or Tester but it still doesn’t work.

Possible solution 2: Make sure that your wall outlet is operational with any other electric home device (working lamp, hair dryer, TV etc). Also check AC power cord and DC cables connection. Everything should be firmly attached to proper slots. Also check “I/0” power switch at the back side of PSU. It should be switched to “I”.

Note: Do not plug 6+2 pin PCI-E connector to CPU 8-pin slot (usually suited on motherboard near CPU socket). You should plug there CPU 8-pin or CPU 4+4-pin connector. Otherwise your PC or PSU may be damaged.


Symptom 3: I have properly plugged AC power cord to the working wall outlet and modular cables to my motherboard (in case of Modular PSU), but when I press “Power” button on my PC nothing happens.

Possible solution 3: The “Power” button lead can be pulled off the motherboard. This lead is usually labeled PW-ON or PW and it reaches from the front the PC case to a small block of metallic pins for case connections to the motherboard. If it is so, connect the lead properly (check your motherboard manual for direct istructions).

There is also possibility that the “Power” button is broken. To check it you need to disconnect the button from the motherboard and try to turn on your PC by shorting corresponding pins with screwdriver.


Symptom 4: I have everything properly plugged but still can’t turn on my PC.

Possible solution 4: Your motherboard can be damaged. There are several options:

  • You can try to turn your PC on with another PSU (for example, your old one);
  • You can try to check your new Seasonic PSU with another motherboard or PC (if you have one);
  • You can try the Jump Start (also known as Paper Clip test) – read instructions here.

There is slight possibility that your motherboard is incompatible with Seasonic PSU, while both – motherboard and PSU – can perfectly work with other components (even with same models or series). We recommend you to check both PSU and motherboard to find this out.


Symptom 5: I have everything properly plugged and my PC seems working, but monitor screen stays black.

Possible solution 5: The proper indication of working PSU are LED power on light (if it is properly attached to your motherboard) and rotating fans on CPU, graphics card and motherboard coolers (if your system has them). Monitors are powered independently, so check its connection to wall outlet as well as its connection to your video adapter.


Symptom 6: System seems to turn on, but after series of beeps it shuts down or not responding at any actions.

Possible solution 6: A single short beep means the POST (Power On Self Test) test was successful and the CPU, memory and video adapter are all OK. All other kinds of boot-up beeps from motherboard point at hardware problems, usually not related to PSU.


Symptom 7: Sometimes my PC can reboot or shoot down all of sudden.

Possible solution 7: If this happens after running high-demand applications or games, your PSU might not have enough wattage to power your PC and OverPower protection turns it out. Please, check how much energy does your PC need. Another possible reason is overheating. Check your PC case placing as well as its ventilation grills. If PSU power is enough and temperature is OK, you can try to check DC voltages, but Seasonic products are well-known for excellent voltage regulation under all loads, including 120% overload. Therefore, your problem is most likely is related to some other PC component.


Symptom 8: PC is on and running, but I hear some noise from my PSU. Is this normal?

Possible solution 8: First of all you need to locate noise. Remove side cover of your PC and make sure that noise is produced by PSU and not by some other component (like HDD or one of cooling fans). Please note that normally under low load (less than 20%) fanless and hybrid power supply units should be completely noiseless from 1 m distance. If you get closer, you might hear subtle electrical sounds, and if you add more power, PSU fan will rotate faster and become louder. Your PSU fan might produce unusual noise if something got stuck in ventilation grille. In this case try to remove foreign object, but don’t disassemble PSU or your warranty will be void. Also avoid touching internal components of your PSU even if it is disconnected from wall outlet – you might get shocked by remaining charge. All other kinds of noise from Seasonic PSU are abnormal and are a good reason to use our RMA service.


Symptom 9: My PC is up and running, but PSU fan is not rotating.

Possible solution 9: First check your PSU’s fan control system. Seasonic’s patented Hybrid Silent Fan Control systems and S3FC switched to “Hybrid” mode are semi-passive, which means that under low loads PSU fan won’t rotate. This is normal. If your PSU has S2FC fan control system, or S3FC switched to “Normal” mode, please, check if there’s some object getting in the fan’s way. If everything seems OK, then most likely your PSU fan is damaged and you need to use our RMA service. Do not disassemble PSU or your warranty will be void. Also avoid touching internal components of your PSU even if it is disconnected from wall outlet – you might get shocked by remaining charge.


Symptom 10: I smell burning from PSU.

Possible solution 10: Make sure that you smell it from PSU and not from some other component. If it is so, do not attempt to fix it by yourself. Address our RMA service instead.


If you have tried this guide but your problem wasn’t solved, feel free to contact us or your retailer for RMA service.


Note: Avoid any operation with PSU and within your PC when AC power cord is attached to wall outlet. Most of Seasonic power supply units are always live when plugged in.