Solved Black screen with nothing, tried thousand ways on google

Hi, I need help here. I have been searching on google and reading several articles trying to figure what's going on. Here is my situation.

I have a Sony laptop, model number is PCG-7142L. This is a Windows Vista Home Premium OEMAct system. Service tag is C6U0K0HG. Everytime I turned on the power, I can see the power LED light turned on (I can hear the system was running) and within 5 second, the light turned off (with a very tiny sound and then no any sound at all) and then in a second, the power LCD light turn on again. However, nothing showing on my screen. I mean nothing. not even showing the mouse arrow.

I have tried to hold F12 or F8 or "shift" Key and almost all keys on the keyboard but just nothing happening at all. I also tried to hook up another desktop monitor because I suspect the problem was my Sony Laptop screen was dead but still showing noting on that desktop monitor. I also tried to take off the battery and unplug the power for days and re-start my laptop, but nothing.

Here is probably my last hope before I throw my laptop to the wall. Can someone help me here.

Hi and welcome to the forums.

Do you have your laptop plugged into the charger when you try to start it up?

Yes, sure I did that and I done the discharge electricity thing too.

Good to see that you take care of your battery with the discharges.

This time at start-up, do not "hold" the F12 or F8 button, tap them repeatedly (several times) untill your BIOS screen will come up.

Do you have another computer or laptop, along with a USB by any chance?

I also did the tap thing too (F12, f8, and others). I didn't know which button I hit but there was one time, the screen did show and everything was normal so I took the chance to re-updated the bios but when I re-strat the laptop, it went back to same, black screen and the trick that I used didn't work no more.
Yes, I do have a desktop and another laptop available, all with USB ports. what I need to do next?
thanks for replying.

changkuotai said:

I also did the tap thing too (F12, f8, and others). I didn't know which button I hit but there was one time, the screen did show and everything was normal so I took the chance to re-updated the bios but when I re-strat the laptop, it went back to same, black screen and the trick that I used didn't work no more.
Yes, I do have a desktop and another laptop available, all with USB ports. what I need to do next?
thanks for replying.

Click to expand...

I think the button for your laptop is F2, try to tap that on the startup.

You need to access the BIOS (find the right button) before I can help you further.

Try these buttons:

[ESC] [F2] [F8] [F10] [F12]

Hi Windows8, after reading your post, I tried to re-start and continue tapping ESC, F2, F8,F10, and F12 one by one but still not working. pretty upset. do you think the motherboard is dead?

changkuotai said:

Hi Windows8, after reading your post, I tried to re-start and continue tapping ESC, F2, F8,F10, and F12 one by one but still not working. pretty upset. do you think the motherboard is dead?

Click to expand...

I don't think that the motherboard is the problem, I just think that your laptop has an unusual button that is used to get into the BIOS.

Try to restart, this time press [DEL]

still not working. I also tried "Shift" this time as well.

changkuotai said:

still not working. I also tried "Shift" this time as well.

Click to expand...

Hm. I'm not sure what to say right now.

The computer won't start, just a black screen with the power light on?

Does it show the make of the computer at start up?

for example:

Windows8, thanks for trying to solve this problem for me.

No, not even reach to that part. I would be very happy to see some lights on screen coming out.
it is just black, nothing at all. only can hear very tiny sound when I turn on the power and then dead.
I have no clue what went wrong.

I think you should take it to a computer shop, my guess is that it has to do with your power, perhaps the hole that you plug the charger in is not working well or maybe the charger isnt good.

If not, perhaps then your motherboard has cracked if your laptop ever fell or been hit.

Good luck trying to fix it, don't throw it at the wall though, its a nice laptop!

I know, I like this laptop a lot, that is why i keep trying and hoping suddenly once day, when i push the power, everything will be fine (stupid me). I tried to take the battery out and use only use the charger as power source but not working and I also tried disconnect the charger but only use the battery as power source and guess what, still not working.
Thank you for your help. I guess have no choice but to bring this to a computer store and hope that guy knows computer a lot.

If you have some spare time and a small screw driver, it won't hurt if you take a look at the inside of your laptop, just to make sure that nothing is broken.

Interesting, haven't tried that part yet. let me do it now. thanks for this tip.

Windows8, you know what, I unplugged the charger and insert the battery back and unscrew the back panel (the little square panel) and then just out of curiosity, I hit the power key and now the computer is on and now I am on the welcome screen.
I was so happy to see that coming so forgot to hit the F2 or F8 or F12

Lol, thats not a problem at all.

Try again and then try to press the correct button.

to enter the BIOS, now what should I do next?

Forget the BIOS for now, just sign in normally and see if you can browse the internet without crashing.

In order to get to the BIOS, (look at the picture i posted before), Just a few seconds after you power on, it will say "Press F2 for boot options or F12 for advanced settings" or something along those lines.

now I am in the advanced boot options, there are
repair your computer
safe mode
safe mode with networking
safe mode wth command prompt
enable boot logging
.......
so which one I should choose? please advise.