Solved! HP DV6700 Issues

[someguynamedmatt]

I've recently been asked to do what I can and fix a faulty HP dv6700 laptop. It's been hit by the same problem everyone else is having - power on, then abruptly shuts off about a second later, and cycles through that until you either unplug it or press the escape key. Black screen the whole time.

I've got a feeling that fixing this is beyond my power... both sticks of RAM were tested as good, the CMOS battery was pulled + reset, tested with no RAM/HDD whatsoever, all with the same results. I'm assuming that it's safe to say that there's a problem with the power circuit... is there any way whatsoever to get this thing back up and running? I know that the previous owner was saying that the DVD burner would randomly start running at full power for no reason whatsoever before the whole thing stopped working...

Any ideas? HP support is absolutely, utterly worthless (I hope they read that) and refuses to even admit that there's a problem here...

Much appreciated.
-Matt

 

[someguynamedmatt]

From what I've heard, it's going to take a solder reflow in order to get this thing to work right, which I really don't want to do. I figure it would be worth trying, though... it's not like it can get any worse than it is right now...

 

[WR2]

Which model of dv6700 is it?
One of the Nvidia 8xxx graphics chips?

 

[someguynamedmatt]

It's a dv6809wm.
http/www.newegg.com/Product/Product.aspx?Item=N82E16834147784
That seems to be what I have... I honestly can't tell you which graphics chip it has without getting it fired up, which is a little hard to do...

 

[WR2]

NewEgg says the GeForce 7150M with the AMD CPU.

I think you're tried all the usual troubleshooting.
Before trying anything else you want to take the HDD out and attach it to a PC and rescue all the personal files that are important to you.

 

[someguynamedmatt]

Already done. Everything's been pulled off of the original HDD. Makes me glad my CM690-2 Advanced has an HDD dock on its top...

What I was thinking about doing before I get into any actual repair was trying to run Ubuntu off of a Live CD, and if I can hold it stable long enough to get it booted, I might be able to run a graphics benchmark with it wrapped in a towel/blanket to purposely overheat it and see if it helps any... I know I've heard some people claiming that it worked for them, but I don't really have much faith in said people, nor do I really think it would do anything...

 

[WR2]

I keep a couple of the Live Rescue CDs around just for that type of testing.
Attaching an external monitor during testing might be useful as well.

What works for some people might be down to 'just luck'. Still not sure what the actual problem is on your laptop.

But if you do have a loose solder joint a 'solder reflow' might work. We just have no data on how often it's successful and how often it fails. We usually hear about the success, but not all the failures get reported of course.
[Solved] What is a reflow? (Laptop Repair)
http/www.youtube.com/watch?v=G65-ncBxdHA

 

[someguynamedmatt]

Yeah... I can only imagine how many people try this to their old, dead motherboards/video cards just to see if it works, and it doesn't. Oh well - just like they said, dead parts are just that: dead. No harm done in trying.

I've got a DVI cable out the back of my rig's 1080p monitor just for things like this - makes me happy it's so easy to switch sources on this thing.

Looks like I'll try reflowing it then. I'll have to find their disassembly manual for this, but once everything's done, I'll be sure to let you know how it went.

 

[someguynamedmatt]

UPDATE:
After I spend the day doing hard reset after reset, it apparently heated up enough to be stable (just an assumption... only ran while hot). I managed to run both Prime95 and FurMark on it at the same time, which must have done something strange to it because it appears to be booting normally now.

Should I go on with this and overheat it further? I know this is a temporary fix at best, but it's worth a try... is there a safe temperature for the CPU + GPU on this thing, where I should be afraid of doing more damage than good? I mean, I could've cooked an egg on the keyboard while it was doing this... it got it fairly stable, though, so it must have done some good.

Seems to be running both Windows (HDD) and Ubuntu (Live CD) just fine, and doesn't crap out during a non-overheating Furmark session...

 

[WR2]

Before you dive in with disassembly / reflow / reassembly (which have obvious risks) I'd give it a week or so with some further testing.
Use the basic tasks you'd be doing anyway and look for any signs it might not quite be there yet.

 

[someguynamedmatt]

Sounds like a good idea. If it still has this much life in it, then I'd say it's not worth it ATM to try something like a reflow and risk completely killing it beyond repair.

I had FurMark reporting 99 degrees (c) on the GPU before I decided to pull the plug and let it cool before it started doing damage to the CPU. As far as I've seen since then, it seems to be about as stable as it was before...

I'll test it out for a few days and knock it around a bit to be sure it's dependable enough to be put back into use. Nothing too drastic, just something a little bit tougher than daily use.

 

[Chaingun_58]

I have recently acquired both a Compaq f572us with a no boot condition just as you've described, as well as a dv6929 with no wireless (they are basically the same computer), also another symptom related to the rampant overheating these boards suffer from

disassembly on both was very straight forward, after tearing down the f572us i did a reflow on the video and cpu, as well as replaced the thermal compound on the cpu. a few slight bends to the heat pipe also allowed it to make direct contact with the gpu, instead of the lousy thermal pad that was on it it has Arctic cooling mx4 as well, the temps after the first solder but before the cooling system changes were idle 78 on the gpu, and 65 on the cpu. After reflowing a second time, and modifying the heat pipe and thermal compound setup i have an idle average of 68 on the gpu and 51 on the cpu. It has continued to work for several weeks now without spikes in temp or any indication that it is not booting normally.

i have prepared the dv6929 for a similar treatment and i'll let you know how that goes.

Long story short, by heating the hell out of the laptop (xbox, ps3, whatever) you have already effectively reflowed the board, only in the wost way possible. A reflow should be done carefully and in prepared sections which are the source of the issue, like the gpu and cpu socket. the towel method can heat and desolder even more than what was originally damaged. If you choose to do a reflow, on these models i'd recommend only doing around the gpu, cpu, and network controller with 5 minutes between each section, and 20 to let the board cool before flipping it over to do the other side.

 

[someguynamedmatt]

Yep... sounds good. It just died on me again after my makeshift overheating session, as was expected. Yeah, you're right... I basically just overheated everything in the laptop instead of just what needed to be done. I've got a good feeling I just reflowed the CPU socket area, whos heat just happened to spread to the moderately hot GPU in order to provide a temporary fix.

I'll be doing a complete, correct reflow of it in the near future, along with adding some of my good old Arctic Silver 5 in place of whatever crap HP put on it. I'll be sure to tell you guys how it turns out. I'm absolutely sure, though, that the nVidia chip is the problem here after several days of rebooting and failing to do so...

I'll be sure to tell you guys how it goes.

 

[Chaingun_58]

Avoid artic silver on laptops, they have uncapped chipsand the conductive compound can short them out I recommend arctic coolong mx4 or another ceramic basedcompound as it don't conduct electricity also you will need to introduce some slight bends into the heat pipe to get it to directly contact the gpu so you can get rid of the crappy thermal pad there. The gpu is the main issue in these combos running between 65 and 90 degrees on average you should shoot for about 70 on the gpu at idle

 

[someguynamedmatt]

Yeah, that's true now that you mention it. Wasn't really thinking of that at the time. I'll be sure to use some of my spare Ceramique instead... I have about ten different types of thermal compound laying around. I'm sure I'll be able to work something out with the heatpipe - I'm pretty competent when it comes to smaller modifications like that.