I recently rediscovered the fun of custom building computers, and after a few months of researching cases and parts, I set the goal of building a fully liquid cooled mITX system in the absolutely gorgeous InWin 901. I had originally tinkered around with the idea of going with the NCase M1, but despite the simple beauty of that case, I really wanted to build in a case that would showcase the guts of the system. Herein lay the first challenge: finding a silver InWin 901. In Win recently decided to supply north america only with the black version, so after calling their north america headquarters for a few weeks, they were able to find a silver one in their warehouse (thanks Allen!). Granted, it cost me $60 more at $220 (newegg sells the black version for 160), but it was well worth it.
Building an effective water cooled system in the InWin 901 posed quite the challenge considering that without serious case modification, there was only room enough for two radiators: one 120mm and one 92mm. Furthermore, it was impossible to cool both the CPU and Video Card using AIO setups. I considered dual AIO (something like a NZXT Kraken X61 for the CPU and an MSI or EVGA Hybrid GTX 1080) when I was into the NZXT Manta at the early stages of my build planning, but once I realized I couldn't pass up either the sleek form or the challenge of the InWin 901, the only option became creating a custom water loop.
The first component I would need to plan carefully before buying was the GTX 1080. Although I needed a little of space between the end of the card and the front of the case to allow room for the water loop piping, the length wouldn't pose a problem with 12.5" of length to work with. Depth, however, was an important issue considering that if I were to install a waterblock on the video card, the intake/output ports would extend ~1.5cm out from the edge of the card. After looking at the dimentions of all the available 1080s, only the Gigabyte G1 Gaming didn't extend beyond the PCI slot screw mount. Thankfully EKWB released a waterblock for the G1 in June ('16), so I went ahead and bought both the waterblock (in clear plexi) and the corresponding backplate in black while I waited to find a good deal on the Gigibyte GTX 1080 G1 Gaming. I ended up gettign it for $575 through Jet.com using their 15% first time customer coupon (as well as some other components)
In order to find the best radiator strategy, I looked at a few other 901 builds, and decided the best options for radiators were the 92mm Black Ice Nemesis, which, at 54mm deep, fit perfectly between the inner black metal frame and the outer aluminum casing at the top rear exhaust port of the case, as well as a high fin per inch 120mm radiator at the intake port in the front of the case. I spent a good amount of time searching for the right fans and settled on Noctua considering they manufacture the best high pressure 92mm fan as well as an industrial grade 120mm fan. I was initially reluctant to go with the Noctua fans because I couldn't stomach the horrible tan and brown color, but after weighing the risk of creating an unbalanced fan, I decided to paint the noctua fans black. They turned out well and I can barely hear the fans.
I wanted to ensure enough airflow through the case, so decided to make some minor modifications to the inner black frame to allow for two additional fans: 1. A second 92mm Noctua (mounted to the top under surface of the inner frame) that acts as an intake that mirrors the exhaust across the rear 92mm radiator, and 2. A second slightly less powerful 120mm fan (mounted below the video card, behind the 120mm radiator, over the opening to the PSU compartment and its exhaust fan) to provide exhaust pressure that mirrors the 120mm Industrial Noctua intake fan that pushes air across the front radiator. I then connected all of the fans using a unifying PWM/Molex splitter cable. This cable split a single PWM plug from the motherboad into four 4-pin connectors while powering those four PWM fans from a single Molex connection. Only one of the four PWM plugs has a 4th pin, meaning only one will transmit RPM information to the motherboard. I chose to connect the 120mm Industrial Noctua to this port, as I suspected this fan would be the best measure of overall heat dissipation via the radiators. How this fan setup therefore works is that depending on the CPU temp, the motherboard will read the RPM of the front fan, make a determination of what percentage of the max RPM that fan should run at, and then tell ALL the fans to run at that set percentage of their max RPM. Having identical 92mm intake and exhaust but slightly higher flow 120mm intake compared to 120mm exhaust means that for any RPM, the system pressure will always be slightly positive.
As far as the waterloop was concerned, I didn't have room for a separate pump and reservoir, so went with one of EKWB's pump reservoir combos. Similar to what I'd seen in a few other builds, I used industrial strength velcro to attach the pump/res to the HD cage. In terms of piping, although far less expensive, I didn't want to bother with bending tubes, so I spent hours drawing up various schematics of how to run hard tubing with 90 degree (and a few 30/45/60 degree) angled fittings for 12mm hard acrylic tubing. I also wanted to build in an intake and drain port, and was very pleased with the result.
I chose a motherboard that had an M.2 slot for a Samsung 950 Pro, and while it would fit, there would be little to no airflow across it. I therefore bought some enzotech copper heatsinks to provide some passive cooling as I had read that it was extremely effective.
Overall, the InWin 901 provided a great challenge, is beautiful, and if you aren't limited by budget (which I probably should be), it can house a monster. I have never overclocked before, but once I get the system settled, I will do my research and see how hard I can push it, but I neither have the desire nor do I think the water loop has the capacity to overclock this system to its limit. I''ll post some Delta Ts when and if I do that intense of testing. Till then, I hope my build inspires more people to build in the InWin 901! Thanks