Installation and Lighting

Installing the Phanteks Glacier G4090 GPU block for your specific GPU begins with removal of the stock cooler. In this case, I had received the PCB only for this water block roundup and it's quite something else to behold in person. For those curious, we have a full review of the ASUS RTX 4090 Strix here. The included manual also goes over the removal of the stock cooler if you were not sure about it. There are no pre-applied thermal pads or paste here and you will have to identify, cut, and install the various thermal pads on the block and backplate yourself. The contact surfaces are at least easy to identify but it's still not as simple or fool-proof as a few other options we have seen. On the other hand, Phanteks does something clever by using a tiny support bracket you first install to the block on the top. This allows you to get some extra support from the I/O bracket on the GPU while still not needing to replace the entire bracket as Alphacool and EK do. The rest of the installation is straightforward—carefully orient the block from the back and place it over the PCB. Flip the assembly over carefully on a box, such that the I/O bracket hangs past the edge and does not prevent the block from making good contact. We see now that the block is much longer than the PCB with that extra section on the right effectively sandwiching the PCB too. Secure the block first around the GPU core and then follow the instructions in the manual to install the backplate with the other screws before adding that extra point of security from the I/O bracket to the support piece.


The block fits quite nicely over and around the PCB at this point. You may now choose to plumb the block directly or try and connect the RGB cable which is easier said than done since there isn't much room around that tiny connector we saw before. Instead, I found it easier to just unscrew and remove the bottom aluminium cover to provide full access to that LED PCB and thus connect the first Phanteks D-RGB cable to it. You can now screw the cover back in place making sure that flexible PCB is not loose and then connect the cable to a compatible Phanteks LED controller or, with the provided adapter cable, go to a 3-pin individually addressable RGB LED header on your motherboard to sync the block lighting with other devices. Note how the assembled block still provides easy access to the PCIe power connector as well as the BIOS switch on the GPU PCB.


There are 15 individually addressable RGB LEDs in the Phanteks Glacier G4090AS GPU block for the ASUS RTX 4090 Strix/TUF and this works out quite well despite all of them being in a single row at the bottom. The clear top lights up nicely although the side covers do block off the lighting where they are installed. So you end up with a larger section lit up at the left and two narrower rectangles on the right. I suppose it can be somewhat different from the norm but I would probably stick to using colored coolant in this case. Seen above are some photos and a video showing you how the block would look with the LEDs up and running—please be aware I turned down the exposure since my camera isn't the best for videos, the block is more vibrant in real life.