First Time Custom Cooling with the XH405i kit

Despite being an experienced PC builder, I actually have never attempted a custom water-cooled PC. Watching various tech YouTubers made me feel like I had a decent grasp of the planning and precautions around water cooling but it has always felt like a large commitment. The added complexity of buying several extra parts, individual fittings, and making sure everything was compatible just seemed like a lot of work. There was a level of effort that I wasn’t ready for. But with the H405i water cooling kit a lot of the decision making is already made. I knew all the parts would work together, I didn’t have to worry about forgetting anything, and I could just focus on the building. It seemed like the perfect time to give it a try.

Opening the H405i, I realized the kit doesn’t cut down on the number of products, it just makes it easier to buy them all. It contains a lot of boxes packaged in a surprisingly dense form. After taking everything out, I wasn’t totally sure where to start. I knew that the most important parts were going to be the XC7 RGB ELITE CPU water block, the XD5 RGB Elite pump/reservoir combo, and the XR5 360mm radiator. I decided to begin with the part that was least likely to be moved or adjusted, the CPU block. Unboxing the XC7 RGB Elite was simple. It’s not unlike the CPU block section of an AIO, all I had to do is make sure the block has the mounting hardware and backplate corresponding to the CPU type I was using and screw it in.

• iCUE LINK XC7 RGB ELITE CPU Block
• iCUE LINK XD5 RGB ELITE Pump reservoir combo
• XR5 360mm Radiator
• 3x iCUE LINK QX120 RGB fans
• iCUE LINK System Hub
• iCUE LINK 4-Way Splitter
• 8x XF Hardline14mm OD Fitting (2x Four pack)
• 2x 90° Rotary Adapter (1x Twin pack)
• 3m XT Hardline14mm Tubing (6x 0.5m length)
• XT Hardline Bending Toolkit
• XL8 Clear coolant 1l bottle
• Filling Bottle

At this point it felt apparent I should have a better idea of how my loop was going to be routed. I decided to try and keep the inlets and outlets as close together as possible to keep the tube runs short and easy to work with. Another goal was to minimize the amount of bends it had. I knew that having two bends in a single tube would make things more complicated and I only had two 90-degree fittings.

I ended up using the two 90-degree fittings on the CPU block. It would allow me to use have three single bend runs. First going from the XD5 pump to the XC7 CPU block, then from the XC7 CPU block to the XR5 radiator, finally from the XR5 radiator back to the XD5 pump. By mounting the pump on the middle side fan of the 6500X, the outlet would align perfectly with the CPU block, allowing the hardline tubing to be parallel to the bottom of the case.

With a plan in place, I finished mounting the rest of the hardware. First mounting the included QX fans onto the XR5 radiator and then the radiator onto the case. I noticed the screws for the radiator were unique. They had a wide head, which should help spread the pressure of the screw onto the case, eliminating the need for a washer. Do that for twelve screws and that adds up to a much-appreciated quality of life upgrade.

The one problem I had with the radiator involved the QX fans. When installing the fans and a straight fitting I found that the LINK port was inaccessible, forcing you to use the LINK port on the other end of the fans. You could use it with a 90-degree cable and a 90-degree fitting but with only two 90-degree fittings in the kit, I found them more importantly used elsewhere. This means that I ended up using the LINK port on the other end of the QX fans.

Mounting the XD5 pump was simple but required a little bit of trial and error. There are several different options to mount the pump depending if you are mounting to on to the side or the bottom and whether you mount it to a fan or directly to the case. In my situation, I am mounting on to a side a fan so I used the included mounting hardware designed to screw into the fans. It comes with support for both 120mm and 140mm options so you should be able to mount the pump virtually anywhere.

Putting it together is pretty simple but getting the precise height was a little bit of a challenge. The fan mounting bracket allows for the pump to slide and lock in so it took me a few attempts to get the placement of it just right. I failed to account for the slight sag of the pump as I let go for it to only be supported by the fan bracket. Fixing this required me to unscrew the whole bracket to raise the pump up which was a bit of an annoyance.

With the main hardware in place, it’s time to start the bending. I got prepared by laying out everything I needed. A heat gun, the bending kit, a little bit of water, and of course the tubes themselves. I knew that once I started heating up the tubing I had to keep going until the bend was done so I reviewed the process several times to make sure I knew what to do.

With my tube runs being so short I figured I had enough material to cut the tubes in half, helping the tubes feel more manageable. At the end of it all I still had three full tubes so there’s plenty of tubing to try and hone your skills. Since all my tubes only had one bend, I was able to bend them first and then saw them down to size. This allowed me to worry less about where I was heating up the tubing so I could have plenty of material to handle on either side and just focus on the quality of the bend.

After using a little bit of water to help lubricate the silicon insert, I put it into the hardline tube and began heating it up. Even with the heat gun running at its maximum power I was surprised how long it took to soften, a solid minute or two that feels like an eternity. I took a slow and steady approach, constantly rotating and moving the tube side to side to try and heat up a large area. Once I noticed that the tube was starting to bend under its own weight, I put it into the bending tool to help find that perfect 90-degree angle. On my first test bend I noticed that the tube wants to unbend as it cools. For future bends I held the tube on the bending tool until it cooled all the way.

The sawing and deburring process is straightforward but be sure to do it properly. I didn’t screw in my tubing and ended up a slanted cut. Screwing it down not only keeps the tubing in place but also ensures that it is flat. Another thing I didn't anticipate was when I was sawing a lot of tubing off at once, the excess weight of the tube being removed caused the piece to snap off before I was done sawing, leaving behind excess material. It could be sawed at and deburred down to a usable state but for a cleaner result I would recommend trimming down your tubing before making the final cut.

Some of my tubing ended up a little shorter than I’d like. This didn’t end up being a problem, but a tighter fit would have brought me a little more peace of mind. Even with all the fittings fully secured, I was surprised how much the tubing could shift around. I expected it to be a super rock-solid but there is a little bit of wiggle room. That means that (functionally) your bends and tube lengths don’t need to be perfect. But if you're looking for optimal aesthetics, the length of your tubes does affect the position of the bend and angle of your bend. Cutting a tube down longer than you need then making small adjustments can help solve this.

The filling process was by far the easiest part. It really is as simple as filling up the reservoir, letting the pump run until the reservoir is drained, then doing it again. I was surprised how difficult the filling bottle was to squeeze but other than that it is extremely easy. I had a single drop form outside one of my inlets, but a slight tightening of the fitting fixed that.

After that my first custom cooling loop was complete! It was honestly a pretty nervous experience, but I knew that the only way to overcome it was to just do it. I would tell other people thinking about trying hardline tubing to really take your time. The joy is in the journey and trying something new is exciting in and of itself. The H405i water cooling kit helped this by making it easier to focus on the process of building rather than the complicated part picking.