3M Novec immersion cooling AMD Vega 56/64

[HerpDerp-1]

Hello from Holland,

 

I have a pet project in mind for doing a 3M Novec 7100 immersion cooled PC. I want to have the GPUs (AMD Vegas) fully stripped of their casing and the fan disconnected. What caveats should I expect from that? 

• Will there be any bios problems and a sheer inability to startup the cards in case of stock bios, which expects some sort of consumer (fan/pump) to be connected to the card?
• Should I have a test bench onto which i come up with a flashing sequence that gets the card to one of the non-reference liquid-cooled firmwares prior to dipping them?
• If I get to a stage where the little puppies are actually starting up under a custom bios, will it be possible to use OverdriveNTool with the fan section disabled to do further modifications?

I am very curious about the initial situation where the cards have the stock firmware and whether it's OK to strip them and dip them. What happens then ? :)) My issue is that the cooling solution is rather expensive and also there's a secondary de-greasing solution with which they would have to be treated prior to getting dipped. From then onwards constantly submerging and taking out the cards will kinda introduce all kinds of dirt in the liquid reducing its longevity at a very rapid pace. 

 

 

Note 1: Not a PC, but rather a miner with many, many cards

Note 2: Not a pet project, already a sizeable investment has been made

 

Thanks for reading! Gr, Todor.

[W-L]

9 minutes ago, HerpDerp-1 said:

-SNIP-

Welcome to the Forums!

 

Heaving the heatsink on the GPU isn't a bad thing as it will provide more surface area for the cooling fluid but note that in this kind of setup your tank must be 100% sealed as it's a low boiling point fluid and will evaporate away if not contained. The use of two phase cooling systems is ideal for this as it will keep the fluid sealed and completely isolated. 

 

Removing the fans and such for the GPU's isn't a problem as it's commonly done when liquid cooling, and it won't give an error such as a CPU fan error. 

[HerpDerp-1]

Hi there,

 

Thanks for the swift response!!

 

I'm thrilled to hear that having nothing attached to the fan power connector of the GPU is not a problem.

 

Aside from that problems stemming from conventional physics are abound at this point. We are indeed going with the condensation approach, since only then can we reach the advertised heat dissipation reduction costs to the advertised 95% level. So we will not be pumping out the liquid, but would rather have a coil attached to an external body. For dealing with pressure, we're going to go with the "farty" bellow method outlined in 

 

Due to the lack of small, discrete hot plates we're going to be sticking with the copper extender to which the stock fan's cold plate touches, since anything else from the market will be too bulky and will end up eating a lot of space refraining us from having high density. At the same time, due to the HBM2 design being on the "same" chip as the gpu cores, these vegas go up to 120C temp on the right hand side, so its impossible to go without additional hot plates for increasing the surface.

 

The entire rack, our custom power supplies and the pressurised container are still work in progress, but will try to update this thread with some photos in the coming holiday weeks.

 

Thanks for the assistance, much appreciated :):)

 

Regards, T

 

[W-L]

3 minutes ago, HerpDerp-1 said:

-SNIP-

Just to make things a little easier you don't need to use copper pipes a large regular watercooling rad would do the job rather well with the increased surface area and having threaded ports you can easily seal everything to ensure it's isolated from the Novec fluid. 

 

Just to give some ideas Debauer did this and used the bottom portion of a waterblock for increased surface area to help with the increased surface area. 

 

[HerpDerp-1]

I see what you mean. I was trying to find something cheaper from which to scavenge the bottom, but have been unsuccessful so far. What Debauer is using would fit perfectly, there's around 2.5cm gap between the cards. 

 

Initially, we're just going to stick to what the card itself comes with under the fan, or at least that's the current idea.

[HerpDerp-1]

Ah, sorry, now I realise that you were referring to the 2-phase pipes for condensation on the top and not the surface extender. Will consider that. Thanks!

[W-L]

38 minutes ago, HerpDerp-1 said:

I see what you mean. I was trying to find something cheaper from which to scavenge the bottom, but have been unsuccessful so far. What Debauer is using would fit perfectly, there's around 2.5cm gap between the cards. 

 

Initially, we're just going to stick to what the card itself comes with under the fan, or at least that's the current idea.

You might be able to get away with modifying a lower profile heatsink designed for a server CPU to fit onto a GPU such as this.