Compaq M700 - Broken - HELP!

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MB Enthusiast
Aug 7, 2003
Does anyone know where this wire goes ???

When you power up lights flash, but no display - not even an flicker.
Nothing to an external monitor either.

It was working, upgraded form W2k SP2 > SP4, then during reboot, after 2yr old "moved" it off table, nothing.......

Any ideas ?


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That wire is the DC supply to the backlight inverter for the screen. The screen will most likely be displaying something but without the backlight on you have no hope of seeing it.

Be careful, if it's the output from the inverter, you'll have a strike voltage of around 4kV and then a continuous output of around 800V on there. If it's the input you'll only have 12V or 5V depending on which inverter you have.

I can't see clearly which side has snapped in your picture, but I suspect it's the side that would normally go up into the screen.

Hope this helps,

Is it repairable ?

This would not explain why there is no External video, would it ?
Have a look at the M700 support manual from Compaq.

Around page 110 it deals with the inverter cabling and how to route it.
As already mentioned it can carry a HT voltage of around 1000V so be sensible when handling it. If the HT cable comes loose while charged and hits the motherboard it will fry it. On most models the inverter need to be powered for the external VGA signal to be provided.
If either of you are ever in Herts and need a beer...let me know - many thanks.

It turns out that it was the Mic cable....Which is a real pain, as this laptop lives in Mal Pais (Costa Rica), and is used for Skype and MSN only !!!!

Still no ideas as to the dead video..... but when I put it all back together again, it worked !! (and no "spare" screws leftover)
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WLeg said:
It turns out that it was the Mic cable...

Hmm ok... I'll try to remember they've swapped the sides of the data and power cabling on the newer Compaq / HP notebooks then. Why can't they just keep things the same :mad:

WLeg said:
Still no ideas as to the dead video..... but when I put it all back together again, it worked !! (and no "spare" screws leftover)

Fair enough, maybe a loose connection then - the display panels use LVDS signalling so usually have those nasty friction lock connectors on them. Used to have a problem with an old Dell laptop which used a friction lock connector for the keyboard - it kept coming undone while typing so only one row of keys would work!

Glad you got it fixed anyway.

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