Installing the waterblock:
Removing the cooling system :
Now it’s time to install the Alphacool CORE RTX 4090 waterblock. Note that we’ve already carried out a series of benchmark tests. The idea is also to record the temperatures of the various components of our Gainward RTX 4090 phantom. Before installing the Alphacool waterblock, we need to remove the original cooling system from our graphics card.
Here, the task is much simpler than on the RTX 3080 FE, as we first need to remove the 11 screws from the backplate.
Next, remove the eight screws from the PCI bracket.
All that remains is to remove the 4 screws around the GPU chip and remove the PCB without forcing it, using gravity. There are still 2 cables to disconnect and you’re done.
Clean with IPA alcohol and you’re done. To remove traces of thermal paste, you can use a charcoal eraser. This also works well for cleaning anodized aluminum radiators stained by thermal paste.
Installing the waterblock :
Let’s move on to waterblock installation. The first step is to fit the thermal pads and then spread the thermal paste over the chip.
Next, place the PCB on the waterblock and gradually tighten the crosswise screws. At this stage, it’s best to dismantle it again to check the application of the thermal paste.
Here, the application as described in the instructions was not optimal, as can be seen in the image below.
I therefore reapplied some thermal paste. Alas, this was not conclusive, as the first tests produced poor results.
So I disassembled it again and squeezed the thermal pads as hard as I could with my finger. Then I did a cross application. The gain was over 6°C on the CPU and 1°C on memory. The 1mm thermal pads offered by Alphacool in the bundle seem too thick. You might want to consider replacing them with 0.5mm or 1mm ultra-soft ones.
If all goes well, we can reassemble and fit the thermal pads and backplate. The PCIe bracket is placed between the PCB and the backplate.
The waterblock is now fitted. This makes the board very compact. It’s perfect for use in small SFF configurations. The only problem is that the backplate protrudes enormously. This makes it impossible to access the locket on the motherboard. A notch in this area would have been welcome.