Finished my build about two weeks ago and finally had some time to take pictures and run benchmarks (open the images in a new tab for full quality). Thanks again to the members in this thread who helped me with correctly planning the custom loop. This was my first custom loop (previously build was AIO watercooled) so it was a bit more challenging than I was expecting. I'll add some amateur advice later for anyone else planning their first custom loop in case it is useful.
 
Components:

• ASUS ROG Crosshair VIII Dark Hero
• AMD Ryzen 9 5950X
• EVGA GeForce RTX 3080 Ti FTW3 Ultra Hydro Copper
• Crucial 16GB Ballistix RGB DDR4 3600 MHz x4 (64GB)
• Samsung 980 Pro 2TB
• Samsung 960 Evo 1TB
• be quiet! Dark Power Pro 11 1000W 80 Plus Platinum
• Phanteks Eclipse P500A DRGB (Black)
• EKWB EK-Quantum Reflection Evolv X Distroplate
• EKWB EK-Quantum Magnitude CPU Block
• EKWB EK-CoolStream SE 360 Radiator x2
• EKWB EK-Vardar X3M 120mm Fan x6
• Bitspower Leviathan SF Radiator 140mm
• Phanteks SK 140mm Fan

 
 


 
I did +300 memory clock and +125 GPU clock in Precision X1. On average the card runs at 30°C idle and 55°C at full load.
 
 
 
My experience building my first custom loop was mixed. The end result is very gratifying, but it was a time consuming and often frustrating process involving a lot of trial and error. Between planning the loop, figuring out all the right parts I needed, measuring the runs and executing the bends, it is a completely different experience than building a non-watercooled PC. Some of the things I learned from my first attempt might help others who are planning their first custom loop as well:

• Plan for the whole process to take longer than you expect. What I thought would take a week at max turned into months (albeit that was mostly due to waiting for my GPU notification email). I had to make multiple orders for parts because I either ran out of tubing or discovered I needed a different or extra fitting.
• Order more tubing than you think you will need, and I recommended buying the 1000mm pieces instead of the 500mm ones. Unless you have extremely simple bends, it is going to take multiple attempts to get each run right (especially if you are a bit of a perfectionist like me). You might read that if you make a mistake you can just heat up the tube again but this results in ugly, deformed looking bends. If you want it to look clean, it needs to be perfect the first try. The 1000mm pieces resulted in less waste in my experience, I was able to get more runs from each one than the 500mm pieces (you're going to have a lot of leftover small pieces when finished).
• A lot of people online will say that with hard tubing you can just eyeball it. I don't know how this is possible unless all you are doing is a 90° turn and then cut each end to the right length afterward. If the run has more than one bend, the measurements need to be precise. Even if you are off by a few millimeters there is a good chance it won't fit correctly. Most of the tubing I wasted was before I bought the Monsoon Hardline Measuring Kit. It was only $11 on TitanRig and 100% worth it, I highly recommend it. It works best if you purchase their Mandrel Kit as well to take advantage of the center-line measuring approach which worked extremely well for me.
• It is harder than you may think to do an accurate 90° bend, at least it was for me. The molded bending tools (I tried the one from EKWB) don't work very well. I found that using two rafter squares and a 360° mandrel produced the best bends. 
• Not an option for everyone, but if you have a miter saw it works great for cutting acrylic tubing. Makes clean cuts without any burrs or cracks that look just like the factory cuts. A sliding miter saw works best and just make the cuts by pulling the blade toward you instead of pushing.
• Getting a leak tester is worth it. When I finished my build I discovered right away that one of the compression fittings was not tightened enough and I am really glad that I hadn't already filled my loop with coolant before fixing it.
• People recommend placing the drain valve at the lowest point of the loop for a reason. I made the mistake of putting my drain valve where EKWB recommended on the distroplate (even if this is the lowest point on your loop the pump is still below it so not ideal). At some point, I plan on buying a splitter to attach to one of the ports on my front radiator (which is the lowest point in my loop) and moving my drain valve there. Before putting coolant in my loop I flushed it with distilled water and draining it was not fun (in fact the coolant is mixed with a little distilled water because I could not get it all out without completely disassembling the loop).
• Again, I had a lot of success using Monsoon's measuring kit and mandrel kit. It was definitely worth the money and made things a lot less frustrating once I had accurate measurements and a way to successfully execute them. Also consider Titanrig.com and Spartanliquidcooling.com for your watercooling needs, I had a great experience with both retailers. Their prices are good and they carry items that are difficult to find elsewhere.

Grey_Beard
Nice build. Clean. Looks amazing. Seems you may have caught the bug.

Thanks! The end result is extremely satisfying, but building it was time consuming and at times frustrating. I'll be doing a custom loop again for my next build but right now I am in no rush lol.

 
Nice rig.   

Great looking Rig
 
Post some Benchmark scores - when you have time
 
Time for a Mods Rigs page: (password is the same as the one you made for Forums)
 
 
those pictures should help other members bend clean 90 in hard tubing

great job looks sweet

rmorse27
great job looks sweet

rjohnson11
This is one awesome build. 

Thank you :)

Great Build +1 Looks Perfect

Cool GTX
comment & +1 posted in your Mods Rigs page

tattude69
Great Build +1 Looks Perfect

rjbarker
Very nice build !!!! I dont think I would have the patience required for hard line......very nice job!

Thanks!