Why can't my computer power up?

[jake1496]

Hello everyone! I bought a Lenovo PC from ebay.com and a laptop from sourcinggate.com three years ago but hadn't used them since the last year. Then I found I even can't power them up a few days ago. Who can tell me the reason? Thank you!

 

[johnb35]

We need to know what happens when you press the power button. Does anything turn on, like fans or does it try to turn on and then stop.

 

[Jiffyman]

Could be a bad power supply unit. Are these both desktops?

 

[jake1496]

When I press the power button, the display keep black but the power light is burning.

 

[seanspotatobiz]

Does that apply to both systems? Do either beep a number of times while booting?

You should probably create separate threads for each system, so this doesn't get confusing.

 

[spottydog]

Quite possibly it is a bad contact on the RAM.
Oxidisation causes a bad connection.
Pull the RAM out and clean the contacts with a pencil eraser.
My experience has been that if you press the power button, all the lights come on, but no "beep", then it's a bad contact on the RAM.
You don't necessarily get an error code beep.
In some cases bad contacts on the video card causes the same symptom.

 

[jake1496]

I changed the battery and tried again but it didnt succeed.Then I checked the RAM but found nothing wrong.