Water cooling a GeForce RTX 4090 laptop: Eluktronics Liquid Propulsion Package G2 review

The chassis has been completely revised to be easier to use and more user-friendly to service. For one, the orifice for pouring water is now much wider and so a funnel is no longer necessary. Secondly, the water level indicator is now on both sides of the unit and it is much easier to see when compared to the narrower indicator on last year's design. And lastly, all ports are now along the rear for easier cable management and a cleaner look from the front.

Eluktronics has a simple 3-minute video showing how to set up the LPP G2 as shown below. The process is easy as the hoses are magnetized at the ends and so no screws are required. Remember to purge the closed system of air each time you need to reconnect the hoses by holding down the power button on the LPP G2 until the LED turns purple. The video does not say for how long this should be done nor are there any printed instructions in the box, but purging should take no more than a few seconds.

Keep in mind that the magnets connecting the ends of the hoses to the LPP G2 and laptop are not very strong. They can be knocked off by accident somewhat easily and it is not recommended to move the laptop or LPP G2 whenever the pump is running.

We experienced minor leaking on both ends of the hoses during the first hour of testing. The leaking would eventually stop on its own, but it's a bit alarming to see any leaking at all.

The external unit offers no additional USB or HDMI ports unlike on eGPU docking stations. This is because the LPP G2 has no physical data connection to the host laptop; it relies completely on Bluetooth and the Eluktronics Control Center for any changes or RGB settings. This also means that the unit must be connected to AC and cannot run on laptop battery power.

It's important to remember that the external cooling box is supplementary to the internal cooling solution of the laptop — it does not replace the laptop cooling solution. Thus, the dual fans in the laptop will still behave like normal when running higher loads. Attempting to measure the fan noise of the LPP G2 in isolation is therefore not representative of real-world conditions since it is always sitting next to the laptop given the relatively short 24-inch hose.

The laptop will always run both louder and at a higher-pitch than the cooling box when gaming which makes the cooling box almost unnoticeable when under such conditions. When running lower loads like web browsers or videos, the cooling box is nothing more than a quiet hum. You can even turn off the cooling box completely and then turn it back on as needed without needing to change anything on the laptop.

Since the LPP G2 draws power from the same 330 W AC adapter simultaneously as the Mech-17 GP2 laptop, we can only measure the power consumption of the entire system as a whole and then compare it to the laptop and adapter without the LPP G2. Running Witcher 3 with the cooling box active would demand about 309 W vs. 300 W if the cooling box was removed from the setup. The LPP G2 is therefore less demanding than initially anticipated to be within the power envelope of the existing 330 W AC adapter.

Eluktronics is currently shipping the Liquid Propulsion Package G2 for $249 USD as an optional accessory to the Mech-17 GP2 gaming laptop.