Pc automatic shutdown no display no function

That sounds like a hardware problem. Start with the easy stuff. Unplug the PC, open the case, and make sure the RAM is seated properly. Also check that the big power cables going to the motherboard are firmly connected.

If you have two RAM sticks, try starting it with just one at a time. If it still shuts off before you get any display, the power supply or motherboard could be the problem.

Don’t start buying parts yet. Check the simple things first.