It's finally done! This custom loop took about 3 months to plan/gather parts for and two weeks to build. I've learned a lot and now I want to share as much as possible with the SFF community!


Specs:
* Intel Core i9 10850K
* Gigabyte GeForce RTX 3080 10GB VISION OC
* Corsair 32GB (2x16GB) DDR4 3200MHz CL16 Vengeance LPX Black
* Gigabyte Z490I AORUS ULTRA
* 2 x Samsung 970 EVO Plus 1TB
* Corsair SF750 750W 80+ Platinum (custom cables)
* Cooler Master NR200P White (with 3D-printed feet)
* 2 x Lian Li UNI FAN SL120 RGB PWM White
* 4 x Noctua NF-A12x15 PWM Chromax black swap

Watercooling specs:
* Alphacool Eisblock Aurora Acryl GPX-N RTX 3090/3080 Gaming/Eagle with Backplate
* Barrow INTEL CPU water block integrated pump and reservoir LTPRP-04
* Alphacool NexXxoS XT45 Full Copper X-Flow 240mm
* XSPC TX240 Crossflow Ultrathin Radiator
* EK-Tube ZMT Matte Black15,9/9,5mm
* Aquacomputer QUADRO
* Alphacool Eiszapfen temperature sensor Plug G1/4 - Deep Black
* Fittings from EK and Barrow
* EK-Quantum Kinetic TBE 160 VTX PWM D-RGB - Plexi (only used to bleed the loop)
* EK leak tester
* EK Cryofuel clear


Idle temps:
* CPU package: 30-35 C
* GPU: 25-30 C
* Liquid: ~26 C

Port Royale 30 min (max temps):
* CPU: 60 C
* GPU: 54 C
* Liquid: 41 C

Cinebench R20 30 min (max temps):
* CPU: 76 C
* GPU: 35 C
* Liquid: 36 C

AC: Valhalla 1 hour (max temps):
* CPU: 70 C
* GPU: 51 C
* Liquid: 40 C


Custom cables:
All PSU cables are custom made by me. I bought most of the sleeving supplies from the MDPC-X online store and I used 17 AWG cables with their small sleeving. Colors are natural white, liquid carbon and transparent.

The 24-pin cable is sleeved as an extension and then I made a really short unsleeved 24-pin cable at the end. I used double crimping in order to make the sense wires.

The 8-pin cables for my GPU are a bit special. Gigabyte uses a short internal extension cable on their 30-series GPU:s (Aorus card being the exception). The internal 8-pin connectors are not the standard Mini-Fit Jr, they are Micro-fit 3.0 instead. This is the same standard used on the 12-pin on the founders edition, but Gigabyte uses two flat 8-pin connectors instead.

With the Alphacool block mounted, these extensions become visible and I didn't want that. Therefore I matched the SF750 pinout with the pinout for these extensions and made custom cables going directly from my PSU to the internal connector on the GPU. I wasn't able to sleeve these, the connector is simply too small to fit sleeved cables into.

All cables were tested with a power supply tester before install except for the GPU cables. I had no way of testing these, but when I got to them I was pretty confident in my work so I just plugged them into my 3080 and booted my PC. They seem to work just fine.


Custom loop:

Loop order:
CPU - GPU - TOP RAD - BOTTOM RAD - CPU

Detailed loop order:
CPU - EK-AF 90 - Barrow 10 mm extension - EK Torque 90 - GPU - EK Torque 90 - EK Torque fitting - ZMT - EK Torque fitting - EK-AF 90 - EK Torque 90 - TOP RAD - EK Torque 45 - EK Torque fitting - ZMT - EK Torque fitting - EK-AF 90 - BOTTOM RAD - EK Torque 90 - EK Torque 90 - EK Torque fitting - ZMT - EK Torque fitting - EK-AF 90 - EK-AF 90 - CPU


Finishing thoughts:
I was very surprised when I saw the temps I got. A lot of similar builds seemed to run hotter which made me expect at least a 50 C liquid temp and a lot hotter CPU/GPU temps.

I think there are two things that contributed to my temps being so low, the extended feet and the vertical GPU. These allowed me to fit a rather fat radiator in the bottom with push-pull and a vertically mounted GPU doesn't restrict airflow nearly as much as a horizontally mounted one does.

I was also able to make the entire loop very short, which might help flow rates a little bit. I did however use a total of 10 90-degree fittings, so I guess that added a lot of resistance back. I wasn't able to fit a flowmeter so I have no clue what my flowrates are, but as long as temps are fine I don't really care.


Sleeving the 24-pin was HELL. I spent TWO DAYS making that stupid cable. I attempted to sleeve it all the way into the PSU first, but it became way too bulky and there was no way for me to fit the bottom rad with it installed. I took inspiriation from PSLATE and decided to split the cable into two instead, which made things so much easier. The bend is by no means perfect, but I looks good enough for me.


I'm overall very happy with my build even tho it is completely useless. No games are being played on it because I'm just spending all of my time looking at it and playing around with the RGB instead.


Feel free to take inspiration from this post, but please don't trust anything I've written. This is my first time building a custom loop with custom cables and I have absolutely no idea what I'm doing. Do your research and check out other sources before building something like this, or you might end up burning down your house.