The computer turns on by itself when I plug it in and turns off seconds later

Good morning everybody.

I've had a Low-End computer for about 8 years now, it's in great condition, but it's always behaved suspiciously. Whenever I plug it into an outlet, it boots automatically for a few seconds (2 seconds usually) and turns off right away, in that time it doesn't give any video and doesn't respond to any commands and the operating system doesn't boot, only after of that I can turn on the computer normally. As I said, I have this computer for approximately 8 years, it has always been like this, the problem is that in recent days, this time of 2 seconds has become increasingly longer, today it took 30 seconds to finish this process. When it's on, the computer works normally, there's no problem, I play, work and do everything on it, it stays in use for 12 hours straight, and it doesn't cause any problem during use. I already configured the BIOS and tried to change the source, I even changed the wiring and nothing.

Does anyone know what can it be?

Specs:

CPU: Intel Celeron E3400 (2) @ 2.60 GPU: Intel 4 Series Chipset RAM: 2GB MAINBOARD: Pegatron ipm 45 Lga 775 POWER SUPPLY: 250w (Model: I'd know ;-; ) Thanks in advance :)

I have a Dell that does this.

In the BIOS there is an option for what to do on power loss, as in if the power cord is pulled either intentionally or not, then it can either fully boot or not.

In either case the system firmware needs to boot briefly to check what that setting is and either power back down or continue to boot normally. The firmware requires the CPU to run in order to do the processing needed, and hence your system appears to "boot" briefly.

I wouldn't consider this "abnormal" behaviour to be honest, just a slight oddness.