Can you help me [PC shuts down after 5 seconds]

You might not have plugged in the CPU power cable. It would be helpful if you could take some pictures of the inside of your computer and upload them here.

Control your cooler if you not has done that yet.
If it not is attached as it shall, the CPU will overheat and give the computer order to shut down.

Begin with that and come back here again with the result.

/Lifooz

It should not shut down so fast.

Your problem remember me about one of my friends computer, in his case, it was the RAM.

But what it is for you can be something totally different.

Do as one of the guys before me said and move the RAM stick to the right.
unmount one of them so you only run with one RAM stick.

If the cooler sit as it shall and you don´t get any success with the RAM, i´m afraid that you need to unmount the computer-components and try them on a table.

It makes it a bit easier to search for the reason of the start-up fail.

/Lifooz

@Battal82:
Who built the computer?
Have it ever worked since it was built?
What is the entire name of the PSU?

You only need 4 parts at the moment.

CPU+Cooler
Motherboard
Memory
PSU+cable

You can see on the fans if it still shuts down.

It is important that you remove everything else. Almost everything that people thought didn't mater like USB cable, mouse, keyboard and so on and the port they were connected to have been known to cause serious problems.

Your motherboard seems to have a Power button that you can start the PC with BUT first remove all cables that goes from the chassi to the motherboard to be sure that they didn't cause the problems.