Its some HP laptop and when I try to turn it on the screen stays black. But not always...sometimes it works as it should but now I cant get it on anymore. Could someone share their knowledge and help me please?
Even though the given information is too less to diagnose the issue properly, assuming that you are not even able to see the vendor's logo when you turn on the laptop, the problem might be related to the RAM or unlikely the CMOS battery (in case of older laptops).
If you have a single RAM installed, try replacing it by borrowing it from any of your friends for a while. In case your laptop has two RAM sticks, try removing one RAM stick at a time and powering the laptop on. Test both the RAM sticks using this method.
If the problem persists and if you can, borrow a CMOS battery from any of your friends and try using it in your laptop.
If the issue still remains unresolved, the problem might be with the cable that connects your laptop's motherboard to the display screen. In such a case, you may want to take it to an authorized service center for better diagnosis and get it repaired by the professional technicians.