Seriously don't waste your money. Two 420 is pointless. A good 420 should be enough to saturate, and you will only be limited by your GPU itself.
I have two 240s cooling my rig (14 core Xeon and a Titan XP) and my Titan XP tops out at 56c and the card is limited to 2100mhz, end of. Nothing I touch will make it go higher, it is being limited by the firmware locking down the voltage. IIRC there is no way to bypass that, so saturating it is "more than enough" if you know what I mean. IE - there is no point in cooling past what you *need* to make sure you can get max clocks. The rest? it's all artificially limited.
And besides, running that sort of rad volume will likely mean you need two pumps. You can check their headroom, but I would suspect one pump may well struggle.
I run my fans at around 6v. They are absolutely silent, just a very very gentle fssss to assure me they are spinning, if I sit completely still and turn everything off. That is the reason one watercools, so you don't have to live with any sound above the ambient. I mean, I did go to 5v, but at that speed they were not doing a great job (they were hardly spinning in fairness) and I could hear my PSU fan any way (and it's very quiet indeed).
If you want to fit a drain port you can do so quite easily just using soft tubing and a stop fitting. It will have a G 1/4 cap that you remove and the loop drains, though draining a rig is never that simple because of course when you undo that thing there is still loads of coolant trapped within the rads, blocks and so on. For something like that you can use something akin to this.
https://www.overclockers.co.uk/ek-water-blocks-ek-af-t-splitter-3f-g14-nickel-wc-944-ek.html
Or this.
https://www.overclockers.co.uk/bits...cooling-accessory-shiny-silver-wc-079-bp.html
And then something like this.
https://www.overclockers.co.uk/ek-water-blocks-ek-af-fillport-g1-4-nickel-wc-819-ek.html
Which you would have in the lowest part of the case (you need to cut it in or drill a hole). Then you run a fitting into it, then hose, then into the T fitting or whatever junction block and use soft tube and simply hide it.
Personally? I don't bother. All I do is pull out my GPU, undo one of the caps and drain that into a bucket. Then I remove the GPU completely (with a bucket under it, making sure nothing goes on the card itself) and then I blow into one end of the hose until it all wees out into the bucket.
One thing you will need, especially if it's your first time, is one of these.
https://www.aquatuning.co.uk/water-...puter-dr.-drop-pressure-tester-incl.-air-pump
Just trust me, whatever way you choose to plumb your rig you absolutely do need one of those. I will tell you why, too. Knowing how much to tighten up the fittings and how hard to do them up on the hose is something you need to learn to do by feel. No amount of watching videos is going to help you with that. Also, if you make a mistake and forget a cap, or don't do the cap up properly or what not? it will save you an awfully big mess.
Another tip (not sure if WC covered this). DO NOT power your rig on to test the water cooling. Make sure when you are testing and filling it that you use either an external PSU to power the loop's pump, or, disconnect everything associated with your PC from it to make sure that nothing is powered on. A spill onto hardware that is not switched on is easier to tackle than a leak all over hardware with leccy running through it (even though it's supposedly non conductive I wouldn't trust it).
Edit to add. Try and avoid 45' rotary fittings if you can. If you put any lateral pressure on them they leak. That said, so do many rotaries. The only ones I've ever used that won't leak even if you hang on them are Monsoon, but this is what I mean when I say lateral pressure...
The cause of that was this..
OK, see the very small piece of hose coming out of the rad and going from it to the block that runs it down to the CPU block? well basically that hose was too long and was putting pressure on the rotary. Which caused it to create a gap around the O ring, hence leak. Like I said, many rotary fittings are known for leaking so don't use big fat heavy hose.
https://www.aquatuning.co.uk/water-...acool-nexxxos-ut60-full-copper-420mm-radiator
There, that would do it. I wouldn't use EK again. Their rads look gorgeous, but are very underwhelming in build quality IMO.
Bloopers.
Why did I read 2080Ti as 1080Ti? they are still voltage locked though, no?