is my motherboard bad?

[crazyman143]

Hi All,

I have an asus laptop I'm trying to fix for a friend. The symptoms are that it will switch rapidly between charging/not charging when plugged in. It will also sometimes not power on when the charger is in. But, it will run ok on just AC, or just battery. Originally the battery was toast, so I only discovered this after replacing it.

Using my multimeter I confirmed solid 12v from the charger. Broke down the laptop and there is a mobo and a little extra board with the dc jack and some ports that connects to it.

I disconnected this board, plugged the charger in and confirmed 12v on the pins on the DC jack. Then, I reconnected the boards together. Plugged in the charger, checked the pins on DC jack and battery port. Got something like 0.7 volts on both, then the green light on the charger went out, and I got nothing.

thinking something on the main mobo is shorting and killing the charger. Planning to replace the main board. Does that sound like the right thing to do? Anyone seen this before?

thanks

 

[Celery]

That may be the short as the draw was high. Maybe the VR modules.

 

[Rich-M]

Does sound like a short to me and they are tough to pinpoint.

 

[crazyman143]

I still suspect the main board. I went ahead and ordered it along with the DC board just in case. we shall see.

 

[Rich-M]

You did the right thing as long as you are determined to fix it.

 

[setishock]

I would never go to the trouble of replacing the main board. I figure my time is worth 80 to 120 dollars per hour. In the time it takes to open the case and do basic trouble shooting I've spent 2 hours. That's 240 bucks. I could get a refurbished laptop in the low to mid range for that much shipped. Now in your case not being sure what is really wrong, you have ordered a main board and the power jack board. Say 150 shipped.

So far you have invested 390 bucks. Now add in another 1 hour getting the board installed and ready to turn on. Now you're at 510. Put 10 with that and that's what I gave for my HP G7. (Staples was having a blow out sale and I jumped all over it.)

Now if windows doesn't squawk about it being a pirated install, you'll be lucky. It reads the CPU electronic serial numbers and checks the hard ware environment. It creates a hash number it sends to Microsoft along with the key hash numbers. It checks that the numbers are the same from it's internal database every time you turn it on. If something is radically different, it's going to pitch a bitch fit. You'll have to call and talk to a tech or deal with the automated system and get it reactivated. More than likely a tech so you can explain what happened. They're pretty easy going and shouldn't give you any grief.

This why savvy techs call laptops, throw away computers. Mid to low range just isn't worth trying to salvage. You Invest all that time and money when you could have spent that to get a new one. And you get the benefit of a factory warranty.

Just a note here. In the case of high end and/or gaming laptops, they are modularized. For the most part. Those are the ones you pop the hood and have a look. You trouble shoot down to one of the modules that has taken a dump and you replace just that part. More cost effective, less time consuming.

I don't mean to poop in your corn flakes. If that's your thing more power to ya. Go for it. I just use my way as a signal it's time to see what's new on the market in a reasonable range.

 

[Rich-M]

If you ordered the exact same board you won't have an issue with Windows and as setishock so rightly said in most cases Microsoft would approve it manually anyway.
If this is Windows 8 you have the right to move Windows to another oem board as well as that all changed with Windows 8.

 

[crazyman143]

setishock you are basically correct however I'm getting paid a few bucks to fix this and that's still money I didn't previously have, and I like to tinker with things. As for the windows activation, a motherboard swap can trip it but im my experience it will almost always reactivate without a call to MS.

 

[setishock]

Cool! May Murphy be off somewhere else as you work.

 

[Rich-M]

That's a rally we can all respond to!