NickFromSweden

The day someone makes a mATX case that will fit up to 40mm rad + 25mm fans (2x140) in front (and top) with a full D5 or DDC + res combo I'll be the first in line to buy it. It will be perhaps a bit of an odd shape (low and somewhat long). Ideally something along the lines of a Define Mini "S". I have built in both the Define Mini C and the Evolv mATX and they are adequate for AIOs but not a full loop - not with any ease at least.

I put together a build in the Define Mini C and now putting together a build for a friend in Cooler Master MasterCase Pro 3. The MCP3 is roomy in comparison with the Mini C. Aesthetically I prefer FD cases as the simpler in design. With the MCP3 I have to contend with a few angles at the front and on top. But both fit the criteria. Pricing (roughly): FD Define Mini C: $88 (USD) Cooler Master MCP3: $85 (USD)

Tried Elgatos HD60S (https://www.elgato.com/en/gaming/game-capture-hd60-s)? The only snag would probably be the need for a dedicated gfx card.

You should be able to top mount any 120 or 240mm AIO - such as the H80 or the H100i in the SPEC-02. Not familiar with the AMD mounting system - but the AIOs come with hardware to mount the waterblock+ pump combo on either Intel or AMD.

The only AIOs (if one can consider them to be as such) that can be refilled are the EK Predator series, Fractal Designs T&S variants, Alphacools Eisbaer series and the newly released Be Quiet AIOs. I have probably missed one or two manufacturers...but these are the ones I thought of when mentioning refillable AIOs. Fractal Design and Be Quiet use Alphacool components (pumps and radiators) as a basis for their branded AIOs.

Silentwings 3 would be a nice choice. I put a bunch of their pre-cursor Silentwings 2 in a build for a friend.

I went with the EK ZMT in my latest build. A blacked out build with EK fittings in black nickel. Edit: And to appease OP - depends on what look you are going for. I know I prefer monochromatic builds with a minutia of "bling" in the form of fittings, but I shy away from all things RGB. I have a few lengths of Primochills LRT in 10/13 for an ITX build I was looking to put together but I am not too impressed with the overall quality. So maybe go with @0ld_Chicken suggestion and look at Mayhems tubing.

I have tested that case and found it to be inadequate in terms of cooling an X99 + 2x GPU as I need at least 360 + 240mm rads to cool that combination of hardware. Not keen on the 200mm fan they have in it either as I'd like for a more conventional approach of adding 120 or 140mm fans. Aesthetically it leaves much to be desired since switching the 200mm front fan for 120 or 140mm fans leaves gaps around the intake which I find just plain ugly.

Overall, the mATX case market is somewhat neglected when it comes to custom waterloops. But for AIO solutions they all do the job and do it well. Other than that I am in agreement with Coups.

No need to upgrade. In some cases the 4790K beats the 6700K in single core testing. So the 4790K is still very much a viable CPU.

Could you run two separate loops - one CPU + mobo and the other to handle the two GPUs?

I take it you have or intend to put a waterblock on the GPU. So you are looking at either the expandable cpu block + pump combo or the pump + radiator combo. CPU block + pump combos - examples: Fractal Design - Kelvin Series T12, S24, S36 variants Alphacool - Eisbaer Solo or Eisbaer 120, 240 and 280 variants. Pump + radiator combo - examples: EK Predator 120, 140, 240, 280 and 360. Swiftech 220 After that it is finding the fit and finish that suits your build - dimensions and what not. ....and of course your wallet. The Fractal Design and Alphacool versions are cheaper - iirc. And don't forget that you need radiators that can handle the TDP of both CPU and GPU.

Hmmm, I had a look at the arc mini. I guess I'll have to pick one up and do some testing with it. I fear it won't suit my needs, but "don't knock it 'til you try it" right? Would like something along the lines of Case Labs Nova X2M in a larger format.

What components will they be powering? Other than that - Seasonic (if you are opting to go with 80+ Bronze rated PSUs)

Ok, so I picked up an EVGA X99 Micro 2 mATX motherboard and a 5820K on the cheap. With these parts I thought I'd throw together build with a custom waterloop for some minor productivity and gaming. So this leaves me with the dilemma of finding a case to match. More specifically a mATX case that will accommodate a few basic build criteria. After having perused the various manufacturers and a few forums here and there I simply haven't found what I need. Unless someone else would be able to enlighten me. Is it so that none of the manufacturers make a mATX case that will accommodate my needs? So what are my needs, and maybe this is me being just too damn picky, well simply put I need a case to be in a mini/midi tower format with clean uncomplicated lines/design (no frills) to be able to fit a top mounted 360 or 420mm radiator together with a D5 vario pump and 150mm reservoir. My last build was for my personal gaming rig and that was in a Fractal Design Define Nano S and I am planning a build (for a friend) in its bigger brother Define S. I actually reached out to Fractal Design to see if they might make something along the lines of a Define "Mini" S but of course they made a the usual answer: Thank you, your feedback is valuable. Maybe we will look into it. Goodbye. So again - if someone has some insight and could possibly come with a few suggestions it would be much appreciated. Cheers!