Startup Problem with an Hp Compaq nx9005

Hi,
I am facing a problem with an hp compaq nx9005 laptop. When i put it on, the power led start flashing for about 4 or 5 times and stay solid. but the screen stay blank and the cpu fan doesn't turn. Have someone face that issue??

It looks like your computer is experiencing a power failure, but resetting it by pressing the reset button hidden in a tiny hole at the bottom of the computer in the corner near the ram cover could be the first thing you could start with. If that is of no use then take some measurements: After digging the motherboard out of the casing, connect the bare board with a ram chip, cpu and fan only to a lab power supply and measure the current demand for the board, than check the voltages on the main chokes as well as the resistances with respect to ground, and then publish them, so we can help you further.

Can you give further informations on which resistances you want me to test? and what about main chokes?
Thanks

vhunter napisał(a):Can you give further informations on which resistances you want me to test? and what about main chokes?
Thanks

Oh, I see. Well, it would be helpful if you could tell us how advanced you with laptop repairs are and what your knowledge of motherboard layout is. I am asking about that because maybe you are in need of getting some more fundamental grasp of what the computer hardware consist of before making any risky actions on the machine you have been trusted with. So excuse me asking you about that. But, on the contrary, if you are quite confident with multimeter and willing to make progress, I will suggest to find a free laptop motherboard circuit diagram on the internet and study it. You may then look for power sections and go through their design, and than you will at least know what the chokes in question are. Then feel free to ask.

Hi,
Please check the laptop with one memory module only(tested and working) and try it in different slots. Broken connections between memory socket and motherboard is a common issue with these laptops and it may behave exactly as you described it. To fix it you can resolder the socket, even with a simple soldering iron.
Hope that helps.

Paulusplu napisał(a):Oh, I see. Well, it would be helpful if you could tell us how advanced you with laptop repairs are and what your knowledge of motherboard layout is. I am asking about that because maybe you are in need of getting some more fundamental grasp of what the computer hardware consist of before making any risky actions on the machine you have been trusted with. So excuse me asking you about that. But, on the contrary, if you are quite confident with multimeter and willing to make progress, I will suggest to find a free laptop motherboard circuit diagram on the internet and study it. You may then look for power sections and go through their design, and than you will at least know what the chokes in question are. Then feel free to ask.

I am not strong as you people in laptop repairs, but i know how to work with a multimeter. The fact is that english is not my native langage. So when i do not understand something, i use to ask.

Hi, any progress with the motherboard? We all learn here and help one another.
Btw. what is your native language?

Paulusplu napisał(a):Hi, any progress with the motherboard? We all learn here and help one another.
Btw. what is your native language?

I tried Katar83's solution unsuccessfully, i will very soon measure voltages as you told me, and post it to have more help from you people.

I am french native.

Hi,
I was sick for a long time, and i came back with my same problem. I noticed that every switch button power on the computer. And here are measures of chokes:

Near power jack: PL9=19.66V, PL8=19.30V

Big coils: PL1=1.49V PL5=5V
PL2=1.54V PL7=2mV
PL3=1.8V
PL4= 2.5V
just in front of PL7 there is two MOSFET PQ15 and PQ16, and i noticed that PQ16 doesn't deliver any current.

Thanks for helping me