[Dell Latitude 5530] Replaced motherboard, black screen and no POST upon boot.

aguyther

Honorable
Aug 31, 2013
1
0
10,510
Hi everyone, I received orders from my supervisor to install a new motherboard on this laptop for a client. I installed the new mobo, hooked up the bare minimum (SSD, RAM, CPU, and verified that all connections are indeed plugged in and solid.) After around 2 hours worth of testing the laptop this is what I have encountered:


  • Power button LED lights up upon boot.
    On the mobo their are three LED's labeled LED1-3 in descending order on the mobo near the heatsink. When I press the power button, LED 1 flashes briefly and the other 2 remain unlit.
    The heatsink does not spin upon boot.
    When holding the power button to power off the laptop the heatsink spins up and then the PC shuts off per normal procedure.
    When I plugged the laptop into an external monitor, the monitor went from flashing the "No source detected" message, to being completely black.
    No POST beeps.

Now here's what I have tried as far as troubleshooting goes:

  • Swapped RAM between sockets, there is only 1 RAM stick.
    Cleaned the CPU and heatsink of old thermal paste and reapplied.
    Tried an external monitor to see if the LCD ribbon cable was possibly borked.

Things that I am assuming that I should try:

  • Reset the CMOS.
    Take the laptop fully apart again and put it back together in case I've missed something that is not immediately apparent.

I'm leaning towards the CPU or RAM considering that those were reused from the old mobo. I would find it hard to believe that a brand new mobo would have a faulty GPU, or that the mobo itself would be faulty. I need to gather reasonable evidence that the problem is related to something other than the motherboard, but I am fairly inexperienced when it comes to this sort of thing as my work typically does not consist of replacing motherboards, especially on laptops. Does anyone have any recommendations as far as troubleshooting or possible causes are concerned?

Thanks,
Andy G
 
Solution
Time to call in the supervisor. It should never do you any harm to admit defeat and if there is power to the CPU, it's better to do that than to continue powering up with no heatsink cooling.

It might be as simple as a stray screw stuck beneath the board and shorting something.
Time to call in the supervisor. It should never do you any harm to admit defeat and if there is power to the CPU, it's better to do that than to continue powering up with no heatsink cooling.

It might be as simple as a stray screw stuck beneath the board and shorting something.
 
Solution