Hello everyone. Over the past decade or so I've relied primarily on AIOs in one form or another for cooling my CPU, with the latest purchases being Swiftech's H320 X2 Prestige, one of the new AIOs that is using brass/copper rads and other custom-quality level elements. Sadly, after a year of working it seems that it has developed several issues and is being sent in for RMA, which leaves me wondering what to do next. I'vew considered buying a cheap-ish air cooler for the interim but I am unsure if it can handle my OC, but as purchasing a typical Asetek type AIO and/or especially another custom-level like the EK MLC Phoenix and/or Swiftech X3 (if it arrives soon) would be relatively expensive, I've considered also jumping into a full custom loop. This will be my first fully custom loop in nearly 2 decades, so while I've followed some of the hardware's development I could still really appreciate some suggestions and help avoiding pitfalls along the way. First some background on hardware. While I intend this cooling system to be based on high quality parts that can expand over time as needed, here is some of my core system components at current as listed in my "Musashi X99" rig. Intel 5960X - My Swiftech H320 X2 Prestige, when it was working optimally, cooled this very well at 4.5ghz all-core turbo w/ 1.3000v , 4.0ghz max cache w/auto voltage Rampage V Edition 10 X99 Asus ROG STRIX Nvidia GTX 1070 (not planning to liquid cool, at least at first) CaseLabs Mercury S8 This is my initial hardware setup, but depending on how things evolve I may end up with either AMD Ryzen/Threadripper Zen+ models in the near future and/or Zen2 Ryzen/Threadripper next year, as well as a new GPU. In building the loop I figure it is best to start with a CPU only loop initially and leave the GPU for later. Regarding cost and equipment, I'm willing to pay for high end parts that have benefit in quality, reliability,features, and possibly aesthetics, but I'll seek a good value. One of the first choices seems to be the selection of tubing and the choice between soft and hard tubing. Given my recent negative experience with what kind of detritus that can clog up a block, the possibility of leeching, plasticizer discoloration and other issues of soft tubing etc... I am wondering if hard tubing would be a better choice? I recall reading that soft tubing is easier to work with and can be secure with good compression fittings, but what types of tubing out there have no plasticizers/DEHP/Phthalates , don't leech, help limit gunk in the line, and ideally look pretty good doing so? I recall Primochill, Mayhems, and EK (ZMT is supposedly better than DuraClear which seems to have many poor reports for durability/yellowing) being discussed as the best options in this category. Are there any others worth considering? Hard tubing on the other hand seems to have some benefits in this regard besides just looking good and reading over comparisons of PETD and Acrylic, as well as more exotic materials like Copper pipe and Glass has been interesting. Assuming I want to avoid bending on my own whenever possible and the excellent clarity, durability, and non-reactivity I figure borosilicate glass is probably the way to go, with good hardline compression fittings of course? Anyone experienced weigh in on modern use of soft tubing vs hard tubing (particularly glass)? Fittings must come next I'm sure. I gather there are different styles of compression fittings for soft and hard tubing so I'll need to use whichever is appropriate. I recall reading that there are special considerations if using glass hardline to be sure your fittings are deep enough to make a good seal. EK, Bitspower, Primochill, Monsoon, XSPC and others all seem to offer compression fittings for hardline (and soft) tubing; are there any manufacturers particularly of note either aesthetically or in terms of function? Or are they all pretty similar in quality and the choice is generally aesthetic? If I end up using glass, I assume i'll need many fittings for various runs and angles so I can use mostly straight tubing save for where there are premade angled lengths available. Choosing a CPU block seems like a good next step. Things seem all over the map here as opinions go, but it seems that certain names come up repeatedly when it comes to high end - XSPC (which seems to have many strong comparative reviews for its latest block), Heatkiller, Aquacomputer and EK , with plenty of others out there too like Swiftech, Bitspower, and more. I notice that EK is something of a staple, with its SupremacyEVO line being loved by some and leaving others disappointed; its quite possibly it is getting close to its end of life though? It seems that the "RGB craze" and Threadrippers arrival has invigorated the design of many blocks out there and even though I won't be buying a Threadripper style block now, its still a good thing. Radiators are of course an important choice for any line. Thankfully, my CaseLabs S8 has the room so I'm thinking of a 360mm rad - I figure I'll only need one per loop. Not really sure about the thickness of the rad; I know I don't want the "slim" versions, but "performance" editions seem to range from 35mm - 60mm in thickness and I suppose I'd be all right with any of those, but I'm not sure if there is significant benefit to one of the ultra thick 50+mm versions versus those a little thinner and if that really varies brand by brand. As for brands, I hear EK, XSPC, Bitspower, and others make quality radiators but I dont know if there is one particular standout or another. Thoughts? Fans I'm sure will depend on the particular radiator chosen, but I've been hearing good things about Corsair (particularly their mag-lev versions), EK, and Noctua, offering plenty of airflow and static pressure while also being relatively quiet. I know rad fans are a large market but if there's any other real standouts that I'm missing let me know. Now we come to the importance of pumps. Last I checked the market has seemingly split into a handful of pumps and upgrades/tops for them - D5 style, DDC style, and a couple of (expensive) separate designs from Eheim and (ultra expensive) Iwaki (?) based Japanese aquarium pumps. I don't really know if the last two are worth it (it seems Aqua uses one of the Eheim style modded for their uses), so I figure most companies have their take on the D5 and DDC. EK, Aqua, Bitspower, XSPC etc... all have some configuration with custom tops preinstalled. Some even seem to have 2 pumps working in serial (or perhaps for separate loops) it seems; not sure if worth it. There are also many others that are integrated with the reservoir which tends to sit atop it. Do you favor the D5 type or DDC type? Which vendors have made for the best quality versions/pump tops? A modern comparison of them seems to be difficult to find. Since we touched on it last I figure to mention reservoirs next. How much does the volume of it matter? It seems they range from only 100ml way up to 300-500ml. How about orientation, horizontal vs vertical? Is there a reason to favor stand-alone varieties or those with integrated pumps? Any particular ancillary benefits or features to look for (fill port style, some internal thing to prevent cavitation/whirlpool effect)? Is glass preferable compared to acrylic, given it seems a few glass res styles have come onto the scene lately? Most of the "big names" aforementioned seem to have various res options; I wonder if those "unique" aesthetic interior types such as the ones that have helix layouts are still popular and if they perform well. Anything else I should know? Fluid is probably one of the last steps, I'd think. There are two ways to go - picking up a premade formula either ready to go or a concentrate to be mixed, or trying to create your own from scratch. For the latter, I've heard that Distilled/de-ionized water is best, but you also need to add some sort of biocide and/or surfactant; I hear some sort of propylene glycol anti-freeze does the trick, possibly alongside "water wetter" A long time ago people used to put a pure silver coil in the res but I wonder if it has fallen out of favor? For official liquid cooling mixes/products, does anyone know of options that work well and won't damage or clog up your kit? Some seem to say that any sort of colored liquid is bad, but others suggest that it is only the colored liquids that have particulate matter (such the Mayhems fluiids that have sparkles or whatever and specifically say NOT FOR LONG TERM USE, JUST FOR SHOWS, IDIOTS!) that are to blame. Mayhems, EK, primochill and others have some sort of fluid and/or additives that seem of benefit at least on paper as aesthetically pleasing and useful coolant. There are also cleaning kits meant for prepping a new loop for first use or cleaning one out between rebuild..do they have any value? Any of these utilities worthwhile and/or safe? So I'm sure I've written more than enough thus far and I'd appreciate the experience of liquid cooling veterans here. I'm sure I'll have more specific questions once I go about picking out individual components. I wanted to ask the community now to make sure I wasn't missing anything given the very large set of possible manufacturers and products out there, especially given the difficulty in finding quality recent comparisons of components by type. Thanks!