GPU no longer seen after ROG laptop teardown

[WeeemRCB]

Hi

I was getting a bit worried with my 3yr old Asus G750JZ running hot and I know it was due a strip and clean.

 

So tonight was the night.

I tore it down to bits, removed the fans and motherboard and took of the heat excahnger to get to the old thermal gunk.

Got rid of all that and reapplied with some Arctic Silver, put it all together and - hey presto it lives

 

But - its not detecting the GPU

I didn't remove the GPU card from the mboard, so there's really only 2 things I can think of that could be the issue

 

1) I shouldn't have removed the rubbery stuff from the components that were around the GPU and replaced with arctic silver

2) The Arctic Silver may be shorting out a component. I put it on clean, but there may be a bit of overspill (I didn't think it was conductive)

 

Looking at another online teardown I think the surrounding components needed a thermal pad of some sort, but when I pu the cooler back on the GPU, I lifted it back up to make sure it had good contact and it all looked good and had spread evenly on all the components that had the gunk on before.

 

Any help or advise is welcome.

 

p.s. I'm surprised it actually works. I've never done a laptop teardown before. Damn LTT putting ideas in my head

[WeeemRCB]

As an aside - it wasn't actually that dusty inside.

But the GPU had almost no thermal compound on the die and the CPU stuff was looking pretty baked and ratty (I do a fair amount of rendering/editing)

[Trekt Nation]

are you currently running on your iGPU? 

[Trekt Nation]

anyway did you put any thermal compound on the gpu when you were putting the cooler back in

[WeeemRCB]

Yes, the display is using the internal graphics at the moment. It looks like it always did, but the GPU isn't seen in Device manager.

The first I saw was when MSI Afterburner wasn't reporting temparatures (I monitor those in the taskbar)

 

I put a healthy dollop of paste on the GPU and when re-fitting I lifted the heatsink and it had 100% coverage on the die, so it looked good.

There must be a cable I've not connected correctly or something.

 

I'll have to strip it back down and go over all the connectors.

Fortunately I took some pictures as I went so I know that they're in the right way, but one must not be seated properly.

[Megalopath]

26 minutes ago, WeeemRCB said:

Yes, the display is using the internal graphics at the moment. It looks like it always did, but the GPU isn't seen in Device manager.

The first I saw was when MSI Afterburner wasn't reporting temparatures (I monitor those in the taskbar)

 

I put a healthy dollop of paste on the GPU and when re-fitting I lifted the heatsink and it had 100% coverage on the die, so it looked good.

There must be a cable I've not connected correctly or something.

 

I'll have to strip it back down and go over all the connectors.

Fortunately I took some pictures as I went so I know that they're in the right way, but one must not be seated properly.

Have you tried checking the BIOS or resetting the CMOS? Perhaps the BIOS set the GPU to disabled.

[WeeemRCB]

5 hours ago, CaptainMike47 said:

Have you tried checking the BIOS or resetting the CMOS? Perhaps the BIOS set the GPU to disabled.

I did look in the BIOS, but couldn't see anything specific to the 880M in there.

It looks like the basic graphics settings are all that's available (and all I can remember seeing before)

 

I didn't reset the CMOS tho - I'm not sure if there are jumper pins like on my desktop motherboard.

 

It's worth having a second look first as the CF reader and the 2 USB ports to the left of the keyboard also don't work and need investigating.

Should be easier/less scary now I've stripped it once already

 

[Trekt Nation]

I think you killed the vram when you were putting thermal paste instead of thermal pads

[WeeemRCB]

4 hours ago, Trekt Nation said:

I think you killed the vram when you were putting thermal paste instead of thermal pads

Yea ... maybe.... that's what I was worried about

When I took it apart, what was on there didn't look like thermal pads, but more like a rubbery, sticky goop.

 

Unlike the GPU and CPU, I only removed it from the face of the other compinents and left the surrounding goop in place

When I re-applied with thermal paste, I put the heatsync back on then removed it and it had spread it over the tops evenly, so there was good contact.

 

I'll retry tomorrow and if it's kaput then I'll have to get another GPU or send it for repair ....

[0x1e]

Arctic silver is conductive, they have tried their best to stop its conductivity but by the nature of silver it will always hold some conductivity.

 

The Vram shouldn't have paste as its primary source of heat transfer. We use pads because the spacing between Vram and the cooler is much bigger than the die and cooler.

Either the paste won't touch the cooler properly or will have a negative effect because of how thick it is. Plus if it's not being squished then there could be air in it which is an insulator.

 

You can buy pads from Amazon or e-bay which are cheap.

 

I would say, take it apart again and make sure everything is connected properly.

Don't over do the paste because it's silver. If it was a silicon paste then I would say put as much as you like.

Put pads on the Vram.

Put back together.