Aspire 5920g - No beep, then stops, but power on

Hi everyone,
Aspire 5920g laptop
Yesterday I was watching you tube and the screen went black and the keyboard unresponsive. I immediately thought it was the GPU as I have had similar in the past, fixed by gently baking the GPU at 100 degrees for ten minutes. However, this time the problem is different. Whereas when the GPU failed you could still see the laptop functioning via the lights and hd spinning, this time there is complete silence.
When I press the power button the lights come on, fan starts and the dvd spins, then the hd. Immediately after that everything stops including the fan, although the power light remains on. There is no post beep.
OK the laptop is very old, but I don't use it a lot now with smartphones and tablets doing most of the donkey work. However, there are instances when you need windows and if possible I would like to fix it but not spend too much due to the age (that's both the laptop and me!)
I am afraid it is something irrecoverable this time, but would like help in case there is a remedy.
Thanks for reading this.

Accepted answers

All comments

billsey

The sequence the laptop goes through at the beginning is pretty simple. When you push the power button power is applied from the battery to the MB. The MB then powers up the rest of the circuit. The CPU initializes and then starts a memory test, if the memory test fails you get an obnoxious constant beep. If the memory test succeeds then the rest of POST starts up with appropriate beeps or screen messages. Your seems to be failing before the memory test starts. That's going to be the CPU, the MB or the battery. Your laptop came originally with either XP or Vista, so it's pretty darn old. Try this, power off and disconnect the battery from the system, then plug the power back in and try turning it on. If the MB is designed to use either battery or AC then it should start up. If it does that's a strong indication the issue is the battery. If it acts the same (fan spins then shuts off) it's a strong indication the problem is more fatal...

Foxinafix

Thanks billsey, a very comprehensive answer. I have just tried your suggestion but unfortunately the problem persists. As you say, it is very old, originally running Vista, but I have updated a couple of times and it suits me for my requirements.
I am just wondering whether there is any other check I make to confirm it is a fatal fault before I take out the hd and give the poor old thing the last rites.