I received this next message late last night after the first message:
 
"Thank you for contacting ASUS Product Support, my name is Christopher. M. I am contacting you from Asus Customer Care as it relates to your RMA case N1707120060.
I understand that you are seeing information on the Water Channel material. We have received information from our internal team that that the material is made of copper.
Regards,"
 
All I can say is it doesn't look like copper to the naked eye. Regardless it took Asus way too long to get back to me with an answer. If they know it is made out of copper why wouldn't they advertise that? Almost all people that water cool would like to know what the water channels are made out of. Even EK is making an all aluminum water cooling kit now. Knowing what the water channels are made out of is extremely important to everyone that water cools. That is the only way to know what water cooling components should be used with the card. 
 
I doubt I will be updating this thread anymore. Hopefully the next potential Poseidon buyer that stumbles across this thread will know, according to the messages I received from Asus, that the water channels are made of copper. Hopefully I have good luck with the Auros 1080 ti extreme and EK water block. I should be receiving them in the next couple weeks. 

This is Poseidon on same board as mine... I would make that better...
I think they fit...
 

 
No doubt their designers are like artists vs high scool students compare to MSI, GIGABYTE.
Completely different level of design. Only when I look ASUS I have no impression that I would do better.
 
Did you found any evidence that water channels are from aluminum.
That's not small mistake, that would not be small incompatibility problem because such corrossion lead in physical damage of hardware.
They are not mad to claim that aluminium is copper. I remember when they show pictures of Poseidon immediately customers starts to ask about that and they didn't say nothing... After some time, 2-3 months example when ASUS start to sell Poseidon people get confirmation about copper. Maybe they changed in last moment if they planned to use aluminum, because I saw at least 5 people who say that will avoid Poseidon only because aluminium. In that moment you couldn't find normal aluminium watercooling parts. 
EKWB launch Fluid series but I doubt that's connected with Poseidon, they would write about that, special because tasks of Fluid is to offer CPU cooling for price of H110i and CPU and GPU cooling for little above 200$. A240G have GPU block he is not planned for Poseidon.
All RIGs I saw Poseidon is in mix with Acetal Nickel and Copper Brass radiators.
I would not build them with aluminum block not even for 2 weeks until other parts arrived.
 
I liked her from first moment, because look as tank from side. We used on normal flat full cover waterblocks and they probably have little better temps. But Poseidon connected on loop is enough to pull max OC capability from card on 50-55C.

Keep the Asus, its so cool. (I even had two in my cart but a friend told me I was crazy.
He was correct.)
Its so cool in fact I dumped two Vega 64s and got 1 asus posiden.
FYI the part the water makes contact with is not aluminum.
Jayztwocents and another youtuber cover the card pretty good.
And there is a breakdown image of the l cooling solution.

I ran some 3DMark Time Spy benchmarks tonight and my highest score was 9224. Core clock was boosting to 2075 and memory was at 12k. I tried to push the core further but it would error out.
 
So max core clock with the new Aorus is 2075 and I haven't pushed the memory past 12k yet. temps are in the high 30s most of the time and have peaked at 41c tonight. I am very happy with these results and I am ready to get back to gaming! BTW, the Oculus Rift and Robo Recall is about as much fun as I can remember! Everyone should jump on VR. It really is amazing! 

This is result from my GTX1080Ti Poseidon, Air Cooling, Gaming Mode.
I say Air cooling because when I connect in loop she auto boost around 40MHz higher.
Instead 1974-1985MHz she boost on around 2012MHz or more on OC Mode.
 
One very cool guy on ASUS ROG Forum give me code for Futuremark 3DMark Advanced to legalize my scores. But I'm very disappointing with Futuremark who charge more and I can't unlock Time Spy Extreme. It's not problem 2$ price, problem is I used to work with cash...
 
This are results before I unlocked him. At least now I will have Firestrike Xtreme and 4K Ultra valid.
Some results are made on default clock processor and memory because of that don't look main score and Processors because my attention was to check GPU properly on default system.
 


 
Time Spy


 
Superposition 4K and 8K


 
Unigine Valley

 
PCMark 10
 

 


 
What, we can't pay RTX series all of us.
I start to build computers 2002-2003 actively, and before that 2-3 years I play games and pay some graphic cards but other helped me.
2018 year will stay remembered as year when I couldn't any more afford NVIDIA high end GPU and same class as mine previous 4890, 5870, 6970, 580, 780 and 780Ti and before that 9800 PRO, 8800 GTX... All of them very up to 760 euro as I paid GTX780Ti K|NGP|N...
Looking performance, graphic processor, power in that moment GK110 was much better than GTX1080Ti or even TITAN X Pascal or RTX2080Ti...
 
In one moment I thought to wait 2 years to price drop and than to buy TITANs, TITAN Maxwell now for 300-400$, than TITAN Xp Pascal... but price of them drop much slower and we could get much bigger fps waiting only regular GeForce to price drop.
I couldn't find better for 580 euro, because looking ratio dollar euro and price of new cards, same is with used that's same as you pay 550$ for GTX1080Ti. Things are simple, you want GTX1080 new or GTX1080Ti used, for that money.
 
I prepared 750 euro before few months with intention to add around 100 euro more for some nice new GeForce range 250W power consumption.
And what NVIDIA offer to me. She show up with 5% better GPU and RT and intention to charge me 900-950 for same performance as I had from 2016.
I previously decide to delay Pascal and wait better 4K performance with 2000 series and now suddenly NVIDIA show up with same 4K performance and some marketing nonsense, RT playable on 1080p. To situation look even worse they didn't give me enough reason to delay even more upgrade and wait something better... That would be nice 60-70% better performance on 4K, 1300 euro GPU, you can't afford but at least you know what to wait.
Now I could wait 25% better unknown period, maybe 18 months to price drop but unknown period, until AMD become competitive...
Pascal costed same 20 months....and I finished on GTX1080Ti.
Other decide to sell GTX1080Ti to spend value of i9-9800X more and upgrade to RTX2080Ti... smart decision, I hope they resolved all problems and all unplayable games on 4K are now completely smooth. Because that was plan, to NVIDIA give us enough performance difference to compensate situation where GTX1080Ti is weak, not some RT still under developing. RT should be extra, not charged reason why NVIDIA is better than AMD, because PhysX is forgotten.