The research I've done on this indicates you have few options.

You should be able to order the cpu liquid cooler through their parts. I've seen some others use a  corsair h60 and it was relatively easy to install

As for the vrms your only real options are a heat putty or pads.

For the gpu. I havent found anything for the Dells oem 3080/ 3090 pcb. We have to consider they are fully custom. Its highly unlikely we will see an aftermarket solution for liquid cooling as there is no one sized fits all. Every different pub will need its own solution. And unless dell hires someone like msi to make one we probably won't see one.

@LDDiamond   For the gpu. I havent found anything for the Dells oem 3080/ 3090 pcb. We have to consider they are fully custom. Its highly unlikely we will see an aftermarket solution for liquid cooling as there is no one sized fits all. Every different pub will need its own solution. And unless dell hires someone like msi to make one we probably won't see one.

The Dell RTX 3080/3090 graphics cards are sourced from MSI. When I liquid cooled my Dell GTX 1080 graphics card, the water block required was "Reference Design" and made by Aquacomputer in Deutschland.

Hey, thnx for the reply!  I managed to get my hands on the Alienware water cooler for the CPU, reclaimed from a tower.  Any idea how this is hooked up?  As far as the plugs are concerned.  I see 1 plug for the fan and one for pump, but does the system TOP fan stay in as well?  Will it throw an error if I delete the top fan?  I assume the rad fan goes to CPU fan header.  that leaves the top fan open if I delete it.

@Rythmicone    Any idea how this is hooked up?

radiator exhaust fan to TOP_FAN

pump tach to PUMP_FAN

CPU_FAN is *empty*

@Rythmicone 

The heatsink design has changed since z370 (R7/8/9) - see photo below of current design. However, I suspect the part number J46J2 heatsink linked in the above post will probably be cross-compatible as far as physical fitment (I suspect cooling capacity is probably reduced, but with a non-K CPU it should probably be OK). 

Note that there is also a second smaller heatsink (top center), I don't now the part number but it has a different mounting system than the main vrm heatsink (center left). 

The MH0HN CPU cooler is the same model from prior gens.  

The Nidec radiator fan goes into the Top Fan header, replacing the AVC fan.  If you leave the top fan header empty I strongly suspect it will throw an error.  

Thank you everyone for your responses, it has been a great help!

it is not cross compatible. they are too short. 

Anyone found a solution to properly cool the Dell 3080/3090 cards? 
I am getting performance limited due to thermals right now. I only have 2 days left to be able to return the system to dell. Hope I can find a solution before having to return. Cheers 

@Dell630  Mentioned his 1080ti was to reference spec which kind of makes sense as Nvidia probably issues a "reference spec" to all the manufactures to design their own cards by. I know ek offers reference spec cards I'm sure others do as well like Corsair. 

I'm still waiting for my 3090 machine to ship maybe I'll post back later unless someone else can chime in.

"I'll post back later unless someone else can chime in."

Just an update.  The VRM heatsink above in the solution (0J46J2) is not compatible with the R11.  The hole spacing is different.  It is for R5-9.  

The VRM heatsink you need for an R11 is N1C1D, $143. Alternative options may be buying aftermarket heatsinks; however, you'd need to close the loop between the two screws otherwise the lack of continuity will throw a startup error if you plug an AIO like the H60 into the board without VRM heatsinks.  

The liquid cooler is MH0HN.  $109 last I checked, which was a while ago. 

N1C1D  HTSNK VR CPU R11 125W

https://www.dell.com/support/kbdoc/en-us/000139589/

PPID (Piece Part Identification) numbers are affixed to specific Dell parts as a means to identify and or track individual components.

PPID 

CN-0N1C1D-08K00-09I-00FH-A00

@DELL-Chris M  would have more information.

Chris since several users including myself want this part is there a way to get dell to sell it?

https://www.amazon.com/dp/B08X3ZTWBZ

CN-01N1C1D-08K00-09I-00FH-A00

N1C1D

We can see from the internal tool that the notation is =

So very doubtful that Dell spare parts could even access it in their tools to sell it.