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View Full Version : Any laptop repairmen in here?



forrest44
26-04-2010, 03:17 PM
So I got a faulty Vostro 1510 laptop from TradeMe.
Now I want to fix it.

It does have the infamous geforce 8400 GPU, however, I don't think this is the problem

What was happening was this:
The laptop starts up fine, only whilst running on battery though.
Once the AC adapter is plugged in, the laptop will continue to run, but only for a short time, perhaps 5 - 30 seconds, before switching off (with a sort of clicking sound, like when you pull the power cable from your desktop).
After this, the laptop will not start again (and shows no battery charging light), until the battery has been removed and replaced.

From memory the battery wasn't charging correctly either.
Also I think the laptop did not power on when the battery was not installed.
Also of note: when the AC adapter was powering the laptop (running), some high pitch coil whine could be heard coming from the laptop towards the corner of where the AC adapter was plugged in.


I thought clearing the CMOS might help, so I removed the battery and held the power button down for 60 seconds.

Now the laptop does not want to work at all. It seems completely dead.



So I'm guessing the problem is due to the power regulation circuitry on the motherboard.

I decided to take the laptop apart, and found an 8 pin SOIC IC, of which the surface appears to have melted slightly. It is a Fairchild chip (I can tell by the logo), but googling various combinations of the part number reveals nothing.

Ideally I need a new motherboard, but a new motherboard would probably be more than what I paid for the laptop.
So I'm stuck. Perhaps I should try a new AC adapter?
If that doesn't work I will sell the various parts off.

Unless you guys have any more ideas on how to make it work! (I am happy with soldering and have a bit of electronics experience)

SolMiester
26-04-2010, 03:35 PM
Hmmm, I had an issue where the ac adapter plug wasnt making good contact with the receptive slot on the motherboard, stripped it down, found a solder break, re-soldered and it went for about 2 min before the dying and a clicking sound when power connected...I gave up after that.....
Sounds like you have a similar issue.....For a technician to strip down and solder you are looking at $300+

forrest44
26-04-2010, 03:50 PM
It's a more complex issue than that. (I've fixed other laptops with that problem). It seems like once you plug in the AC adapter, the motherboard works for a few seconds then malfunctions (See original post). I'm pretty sure the solder joints are fine, it's something on the motherboard itself

forrest44
26-04-2010, 03:51 PM
But I'll have a look tho

SolMiester
26-04-2010, 03:56 PM
But I'll have a look tho

I think you are correct re the solder, however it sounds like a shorting to me...!

Speedy Gonzales
26-04-2010, 04:15 PM
Looks like these have or had a known chipset fault (http://blogs.zdnet.com/hardware/?p=2308). And faulty GPU's. That overheat. And Dell issued a BIOS update for it :lol: As if that's going to fix it

This may or may not fix it (http://forum.notebookreview.com/showthread.php?t=268081). If thats what the GPU is

forrest44
26-04-2010, 05:11 PM
Thanks for the link speedy, I will perform the mod if I get the laptop working again

However I don't think that the GPU is at fault in this case

zqwerty
26-04-2010, 06:15 PM
Try another mains cord, inspect the board closely, using a magnifying glass preferably, for hair line cracks around the pins of the mains input socket, physically wiggle the socket (gently) whilst looking. Do the same for all large mass components on the motherboard i.e. coils and caps and Xmers, plus auxiliary pcb's.

Obviously you would not do this with power on.

Portable equipment (Laptops) often suffer from impact damage due to being dropped and also monkey fingers roughly plugging things in and out, hence the damage alluded to above, you might be lucky and fix it, you never can tell.