Closer Examination and Installation

As mentioned before, Bitspower has several color options and finishes for their mod kits and pump tops, which are sold separately for the Xylem D5. This particular SKU, the Bitspower D5 Vario, only comes in the matte black you see above. I would go as far as to say that this pump SKU was instrumental in making Bitspower even more popular at the time of its launch, with an emphasis on build quality and materials that went beyond a lot of other such offerings. We have a POM top with the Bitspower logo and a threaded aluminium body in matte black as well, in addition to the pre-installed mounting bracket which also matches the entire design thus far. On the back is a metal cover with cutouts for the pump cables and the Vario pump speed control dial, as well as another logo should you forget who made this. There is a sticker on the side that is easily peeled off; however, the cable itself is bare and unsleeved. This is in stark contrast to the rest of the package and a shame given the otherwise impeccable looks.


As it comes out of the box, the pump assembly is on the smaller side of average for D5 pumps, at 89 x 85 x 97 mm (85 x 85 x 90 mm without the bracket) and includes five BSP G1/4 threaded ports on the top. Two each are on the top and front, marked as in and out to ease planning the plumbing route, and a fifth drain port has been put on the bottom. Bitspower includes three of their BP-WTP-C09 silver-shining stop plugs, which sell for ~$4 each, for the three ports you may not incorporate in your loop. The threads are perfectly done, and the POM top feels solidly machined. The same can be said about the aluminium body and mounting bracket, the latter of which has a cutout at the front to accommodate the tubing—or fittings—to the bottom port. There are also four holes to allow you to bolt this down to your case or pump bracket. Off to the side is the pump cable, which only consists of a single power cable terminating in a regular MOLEX plug for your PSU. No RPM monitoring cable here, which has been the case with this particular pump since essentially forever.


The mounting bracket is held in place using two Philips head screws on either side of the pump, and there is another Bitspower logo as well. The bracket has a slight glossy finish, which shows with fingerprints and smudges on it. The body is easily threaded loose too, which reveals the innards of the pump.


The threads on the body are also machined very well, and the knurled ring provides grip when installed or removed. The cover ring takes more diligence to remove, including unfurling the pump cable and routing it out the hole in the ring to begin with. Removing the cover shows—you guessed it—a Bitspower logo! This one is on the back of the pump and otherwise hidden in use. With the body removed, the pump can easily be pulled off the top to reveal a fairly standard volute design on the top. You can see the flow pathway of the coolant as it enters from either of the two designated inlet ports, moves outwards due to centrifugal force and exits through either marked outlet port. The Xylem D5 is not new to us, with the magnetic impeller over a shaft that houses a ceramic bearing to keep things rotating smoothly and a stainless steel body that is accounted for by coolant manufacturers to avoid any galvanic corrosion.


Installation of the Bitspower D5 Vario pump is trivial, and yet we don't actually see any mounting screws or bolts and nuts included. The rubber dampening bracket does help mitigate the need to screw the pump down, especially with downward pressure from tubing, but is a remnant of when pumps were usually mounted to fan-hole spacings with brackets. There are two possible configurations for installation here, vertical or horizontal, as long as the pump body is no higher than the top itself.