So this was my first custom loop, and to anybody thinking of doing the same for their first loop, I have the following words of advice:

DON'T

This was not a beginner friendly build or experience and will need a lot of tools and patience! But that said, I am super happy with how this turned out.

Component specs:

• Case: Lian Li Dan Cse A4-H20 X4
  
• CPU: AMD Ryzen 7 7700X
  
• Motherboard: ASUS ROG STRIX X670E-I GAMING WIFI
  
• GPU: NVIDIA RTX 4090 FE
  
• RAM: G.Skill Trident Z5 NEO RGB 64GB 6000MHz CL32
  
• NVMe: 1TB Sabrent Rocket 4 Plus + 2TB Samsung 980 Pro
  
• PSU: Corsair SF750
  
• Cabling: Custom by me

Loop specs:

• CPU block: EKWB Velocity² AM5 Nickel ​+ Acetal
  
• GPU block: EKWB Vec​tor² FE RT​X 4090 Nickel + ​Acetal
  
• Pump/Reservoir​: EKWB FLT80 DDC + Optimum Tech 3D printed mount
  
• Radiator: Black Ice Nemesis GTS 240
  
• Fans: Noctua NF-A12x25 PWM chromax.black.swap
  
• Tubing: 10/12mm acrylic
  
• Fittings: EK-Quantum Torque Micro HDC 12
  
• Angled adapters: EK-Quantum Torque Micro Rotary 90°
  
• Fan controller: Aqua Compu​ter QUADRO​
  
• Temperature sensor: Bitspower ​Temperatur​e Sensor
  
• Coolant: EK-C​ryoFuel So​lid Laguna​ Yellow

General thoughts, observations on this build:
The hardline tubing was definitely one of the more challenging aspects here. Particularly the run from CPU to GPU where it wraps around the motherboard and bottom of the case, there's still a few bends I reckon I could improve, but I'm not going to meddle with it for now. Perhaps when I next drain the loop I might try tweaking a few, but for now it's fine.

The GPU waterblock was wider than I thought it would be, so Ihad to rethink a couple of runs as I was building it. Eventually I settled on the 45/135 angles you see here, and I really like them vs the plain 90 degrees I have on the CPU side to match the layout of the motherboard. The observant among you may have noticed I've done away with the RGB section of it. I reached out to EK who confirmed that this is fine to do, though they recommend leaving it in. In hindsight, it probably DOES fit with this fitted, but until I next drain the loop I'm happy without it.

Getting the radiator in involed doing some rather unspeakable things to the case to get it inside. It's MUCH wider than I had anticipated, so doesn't fit through the gap like the H100i did. I also originally wanted to use the Phanteks T30 fans, and whilst it DID fit with the T30 fans, I had no way of securing the radiator as I couldn't use the standard radiator bracket. In the end I settled for the Noctua fans and a much easier life in getting it to fit.

Custom cabling was an absolute MUST for this. I've already writen about this on here, so I'll just link the post.

Performance/thermals:
As you might expect, this is a pocket sized monster of a build, but still all hanging off a single 240mm radiator!

Room temperature: 19C

Idle temperatures:

• Coolant: 28C
  
• CPU: 42C
  
• GPU: 29C

Gaming temperatures:

• Coolant: 43C
  
• CPU: 87C
  
• GPU: 64C

Fan speed is controlled based on coolant temperature using aquasuite.

By far the biggest limiting factor with this build is my airflow through the radiator. Removing the top panel drops the coolant temperature (and each component temperature) by almost 4C. So I'm looking at getting a less restrictive panel. Currently thinking a pattern similar to the Sliger SM series would provide much better airflow than the standard drilled hole pattern.

I've also applied a moderate overclock to the 4090, taking the core clock up to 3.03GHz and the memory up to 12GHz, but limited the TDP to 90%. Overall I've seen a gain of about 5% compare to the stock settings and managed TimeSpy Extreme score of ~20,000 for the GPU in this configuration. I've managed to get almost 21,000 out of it, but the GPU alone was pulling close to 600W from my SF750!

Future changes/improvements:
Honestly, nothing major needs improving here IMO. I may swap the temperature sensor for one that sticks a little further into the reservoir. Adjust some of the bends slightly. And try refitting the RGB section of th GPU block. I'd really like to find a way to get those T30 fans in, maybe a custom 3D printed radiator bracked would give me the extra few mm I need? I'd also like a less restrictive top panel! Eventual plan is also to replace the 7700X with an X3D version, when available.

I might also paint each outside panel yellow.

Thanks for reading, chooms!