Coollaboratory liquid ultra on G74SX

[JamesNgkk]

Hello fellow ROGers,

I am contemplating about replacing my oem TIM with CL liquid ultra. Anyone here have any experience with this particular TIM? What I've gathered is that this TIM will corrode aluminum if it comes in contact with it. I know for sure that the contact point of the heat sinks to the cpu and gpu die is made of copper. But my worry is with the gpu part as the copper is surrounded by another metal which is not copper. I will apply the CL Liquid Ultra on the die just like the instructions says but I'm worried it will touch the supposedly "aluminum brace" that surrounds the copper part on the gpu heat sink. Can someone confirm if the gpu die is the same dimensions as the copper "square" on the heat sink? It will be good if the gpu die is smaller than the copper square as it is less risky for the TIM to touch the aluminum brace.

If it is indeed the same size, does anyone here knows if I would to apply a layer of paint to the brace, not the copper square, will it help prevent the TIM from eating the aluminum brace?

Thanks,
James

[Spook50]

I ordered my G74 from XoticPC and had them put Arctic Silver on my CPU and GPU when I ordered it. I have yet to see either get above 65C, and that's with the GPU overclocked, Throttlestop turned on and playing Skyrim or doing stress tests. I'd say between that and how well ASUS designed the cooling system in these, you should be just fine.

Never heard of Coollaboratory stuff before though, so I wonder how it would compare to Arctic Silver 3.

[JamesNgkk]

Mine came with Acrtic MX-4. It was a okay paste but i think its starting to degrade. My temps are slowly climbing compared to when it was still new. I've dusted and cleaned the vents so i doubt it's the dust build up. My ambient temp usually is about 31C to 33C. When my laptop was new, my CPU would sit around 40-43C at idle and my GPU would sit at around 37C at idle. But right now, CPU sits at around 43-45C at idle and my GPU is about 40-41C idle. Gaming on it and you'll see GPU temps climb up to 67-70C comapared to the 60-61C when new.

Though the temps is nothing to be alarmed about, it does show that the paste might already be degrading and needs replacement. So since i'm going to do a repaste, i figured why not go for something that is "better". From what i know, Arctic Silver, IC Diamond, Arctic cooling etc are "soft" paste. After some research, i found out that liquid metal paste would give so much more better temps compared to soft TIMs. If you haven't heard about Coollaboratory Liquid Ultra, you should check it out. From what i have read, it is mighty impressive. Only concern is that as with any liquid metal TIM that contains Gallium, it will eat aluminium and corrode it away.

[Spook50]

Interesting that they're using something that contains gallium. That stuff is definitely bad juju for aluminum. I think we're safe if you give it a try though. Pretty much all non-garbage heatsinks since the days when Alpha dominated (yes I'm old) have at least a copper plate to interface with the CPU/GPU core. I remember reading years ago that copper will transfer heat better than aluminum, but that aluminum will actually shed heat into the ambient air better than copper, so heatsink manufacturers started using copper to mate with the chip core.

Come to think of it, I think our coolers actually use copper plates against the CPU and GPU with copper heat pipes leading to the cooling fans but utilize aluminum for the actual heatsink fins themselves.

[JamesNgkk]

Yea, i'm really really tempted to try the liquid metal TIM out. Now the problem is that it eats aluminium which you are also aware of. I am aware that our cooler uses copper plates but there is a problem. I'm going to try to verbally describe this as best as i can, i don't know if you have actually seen the entire heat sink assembly for the G74SX. If you noticed on the CPU side, the copper plate has a much larger surface area than the CPU die itself however on the GPU side, its a little different. The copper plate seems to be the same size as the GPU die, i cant confirm that but it seems like it is. Another issue is that the copper plate for the GPU is a square surrounded by another metal which i can only describe it as not copper and possible Aluminium.

What all that means is that, while i feel its relatively safe for me to apply the liquid metal TIM to the cpu since there is so much more space where the TIM can "squeeze" out onto which is still copper, I don't feel necessarily safe on the GPU side. I don't know if you can understand what i'm trying to describe. There is a metal brace surrounding the copper plate of the GPU side which is made of an unconfirmed metal which seems like aluminium. Now if the size of the copper plate is the same as the GPU die, then the TIM would not have extra space to "squeeze out" onto and will likely touch the metal brace. That is what i'm worried about.

Do you know if the GPU die itself is the same dimension as the copper plate? Do you know what metal is the metal brace made of? If it's made of aluminium and i still wanted to try this liquid metal TIM, what can you suggest that i do to prevent it eating the aluminium? Paint it? Any help will be greatly appreciated.

[Spook50]

I would expect the brace is aluminum, though I'm not sure the size of the die of the GPU. It certainly looks like the copper plate is small enough to get some of the paste on it , especially when you see the leftover paste in the pic. What I've always done is use scotch tape to mask around the area that the die contacts, then use a credit card to make a very thin, even layer of paste on the plate. That way there'd be just enough to compensate for any imperfections in surface contact, but not so much that it would impede the heat transfer between chip and plate.