I thought I'd share my system with you and some of its genesis, and problems. So early 2019 when everyone did the videos on the new Corsair One units, I really was blown away. Both by the specs and performance of those units as well as the heart attack inducing Sticker Shock for their pricing. I put owning one out of mind, but the idea of a mini ITX build being dual water cooled stuck with me. So I started watching older videos on ITX builds and when I came across Bitwit's video on his HTPC build using the Phanteks Evolve Shift case 2 years ago I came upon what seems to be the solution.

I put together what I've been calling my Custom Half system. So into a freshly purchased Phanteks Evolve Shift case I put the following:

ASRock Fatal1ty B450 GAMING-ITX/AC AM4
AMD RYZEN 7 1700 8-Core 3.0 GHz (modestly overclocked to 3.8GHz on all cores)
Corsair Hydro Series, H60 2018 120mm Radiator
GIGABYTE AORUS GeForce GTX 1070 Ti
CORSAIR Vengeance LPX 32GB (2 x 16GB) 288-Pin DDR4 SDRAM DDR4 2400 (purchased when RAM was still CRAZY expensive)
Seasonic Focus SGX-650 650W 80+ Gold SFX Power supply
System drive is a: HP EX900 NVMe PCIe M.2 500GB
with a Storage drive: Western Digital WD30EURS 3.0TB (old but fine)

Currently the build is sitting around ~$1300, so also about HALF the cost of the Corsair One along with performance. I've been on the lookout for EVGA GTX 1080Ti Hydro card, but haven't found any at a price point I can justify spending for that level of upgrade from existing performance.

I did buy a
CORSAIR Hydro Series H55 Quiet Edition Water / Liquid CPU Cooler 120mm
And
NZXT RL-KRG12-B1 Black Kraken G12 GPU Mounting Bracket For A-I-O Liquid Coolers
to try and water cool the 1070Ti, but the case just doesn't have the room in either configuration to mount that setup.

This brings up the "problem". I live in Phoenix and thermals are important. I can keep the ambient temp in the room cool enough, but this little guy pumps out some heat and when it becomes thermally saturated, the case compounds the problem. The AIO on the CPU is capable enough, its keeping temps under 60, even being torture tested. It is the GPU that is suffering the most. Temps jump into the low 70's under most loads. Under harder game testing, its jumping into the 80's and thermal throttling while the fans scream away trying to ditch the heat. In order to combat this, I have to remove the front panel on the case completely. This extra airflow helps keep the system usable,but thermals are still not great and aesthetically the case isn't pretty. Pics included.

Late last year (2019) I finally got the Phanteks Shift Air Panel and put it on the GPU side, flipped the GPU around and let it pull in fresh air directly. This helped but it still bumps up to the mid 70's running higher end titles.

I'd love to hear your feedback on this one.