after reballing cannot see second GPU

[rookieme]

Ok the failure I have seen it 2-3 times and I'll like to know if someone had the same experience.
To sum up ther are some laptops with 2 gpu [one with shared memory inside the cpu and a second with dedicated memory at a second chipset] like G62 intel models.
When the second one fails the systems boots ok but just before finish loading windows shows black screen - it is classical problem.
The solusion is to reball or replace the gpu chipset.
Sometimes after that the system no longer see 2 video devices at device manager but only the intergraded one.
This is not a software issue.
It seems that something happened during the repair proccess.
Could it be something from the heat?
At those cases I couldn't find anything that could have gone wrong [lifted pads, no proper soldering].

Anyone knows a way to find a solution?
Thank you in advance

[atsio]

Re: after reballing cannot see second GPU

Usually hp's require to flash bios after reball.

[sasser]

Re: after reballing cannot see second GPU

The problem from gpu itself. That cause system cant detect properly the gpu u inserted. I have found the case from lenovo g480 got ati hd3200 and another is also ati. But there seen only second gpu. Replace with new gpu then on my device manager i see two gpu and can boot with first gpu. Reheat again

[rookieme]

Re: after reballing cannot see second GPU

The fact is that I have also replaced the gpu with new one [realy new] and I have this problem.
Until now no bios reflashing was required in order to play after reballing / replacing gpu.

[atsio]

Re: after reballing cannot see second GPU

You will never know until you 've tried it. I had a lot of "new" gpu's from high scored ebayers which were crap.

[rookieme]

Re: after reballing cannot see second GPU

You will never know until you 've tried it. I had a lot of "new" gpu's from high scored ebayers which were crap.

It happens that I own one of them and once I had swapped both GPU and southbridge from my mobo to another working one but the problem remained at mine and the other one had no problem.

So what else beside reflashing bios can I try?
In my opinion something could have happened due to the reballing temperature.
If I upload a schematic can you make a suggetion what to test?

I did uploaded the schematic finaly.

[atsio]

Re: after reballing cannot see second GPU

Check the rom of the GPU