DV6700 Motherboard Swap.

My daughter has been given an HP Pavillon DV6700 which is repeatedly switching itself on and off. I understand this is probably caused by a common problem with the Nvidia graphics chip. I have a DV6000 with a working motherboard and my plan is to just swap the motherboards over. Is this a feasible plan and if so, are there any major differences between the two motherboards?

Many thanks

 

Your DV6700 switches itself on after shutting itself off?

 

When I switch it on, all the blue lights light up and I can hear the fan start running. Nothing appears on the screen. Then after two or three seconds, it switches off and after a further two or three seconds then tries to restart. It then repeats these actions continuously. I can't hear any beeps.

 

Can you get into the BIOS? Press F10 repeatedly after pressing start. The Nvidia issue will shut your computer down, but I've never heard of one restarting on its own with the Nvidia fault. It sounds like the unit is failing to POST and then trying to restart with safe settings.

Also to answer your motherboard question we'll need the model numbers of the two DV6000 series units.

 

Yes, you're correct. Pressing F10 sorts the stop/start loop. Unfortunately, I still don't see anything on the screen (no flickering or anything).

 

If you have the model numbers it would be helpful in trouble shooting your DV6700 and also comparing motherboards with the DV6000. Look on the back of the unit.

Well, if you're out of the start/stop loop with F10, that's a start. Do you hear any beeping? Try shinning a flashlight into the notebook screen to see if you can see an image. Try connecting the unit to an external monitor via the VGA or HDMI port if it has one and see what you get. Also you can experiment a little with the power sources. Try battery only and then external power only with the battery removed. Since you have 2 DV6000 series notebooks, try swapping power bricks. Bad power sources or connections can cause strange seemingly unrelated behaviors. If you know how, you can remove the RAM and see if it will BOOT with only one stick of RAM and/or in one particular RAM slot. Repeat exercise with second stick (that's 4 tries). Last if you know how, remove the CD drive and try again to BOOT.

What we need is to get a BIOS screen and reset the unit to default setting. With this screen we can also get additional unit information. Take your time and check outcomes. Best, Dave

 

Mainboard model number is on a sticker near/under the memory. Looks like 1A2B3D-001 usually.

If the laptop has AMD CPU, then it will have system chipset (nVidia nForce 430) made with same tech as GF8400 GPU. That is just as much prone to failure as the GPU itself.

 

Ok - I tried all of the above without sucess. In desperation I followed a tip I read elsewhere in the forum and stuck the notebook (minus battery) into the freezer for a couple of hours. Thawed it out for 15 minutes and I now have a working computer!! However, I'm struggling to understand the science behind this and whether this is permanant fix or not. Is there anything I need to do now the computer is running in order to keep it running please.

Many thanks for your help by the way. It's much appreciated.

Edit: I've just had a thought. Maybe the moisture condensing on the circuts when the notebook warms up is making a connection (in which case when it's dry, I should still have the same problem).

 

I 've posted this method before as a last resort... but since you are already there the answer is that this is the Nvidia disease. The reason this works is because when things get cold they generally contract. With these units the solder is faulty on the video chip and cracks under heat cycles. We're talking micro cracks here and when it freezes the solder contracts enough to make contact.

When the unit is shutdown it will likely not restart again until you put it back in the freezer. I ran one for two days like this until it finally died. Your unit is now a parts bin unless you want to pay for a new motherboard or have someone reflow the solder. On to the other unit?

First one I've heard of stuck in the start/stop loop with the Nvidia issue, I've worked on half dozen of these or so and they have all had WiFi failure followed by failure to BOOT. ... it's a learning experience.

Sorry it didn't work out for you.