Closer Examination

The Granzon GAISC is a hilariously large CPU block, to the point where it doesn't feel that much smaller than some blocks which have pumps integrated on top. To give you some context, a typical CPU block is about half as tall as this. Add to this the mounting bracket that is part of the frame itself, and you have a chunky block which weighs nearly 500 g by itself. I have to say I am not a fan of the aesthetics even outside this form factor. The GAISC is all black, broken up only by the G1/4" ports, with an industrial design that isn't telling me it is a premium product. Perhaps the mix of aluminium alloy and POM is part of this, but the bigger part is just that the top is just a 2.9" screen taking up most of the real estate. There are two small buttons above, which of course you don't know what they do in the absence of a user manual, and then the two G1/4" ports themselves that are nickel-plated brass inserts in the top. The threading is perfect and the metal used means there is less risk of damaging the block if you overtighten fittings, but the actual plating is not perfect. This is even more obvious on the side ports, which is another way this block differentiates itself from the others, that have low profile stop plugs installed. I will give Bykski props for using the available thickness here to add these side ports—this time threaded in the POM section—and there are arrows up top to help indicate the preferred inlet and outlet ports.


A look from the side shows where the aluminium alloy frame ends and the POM body begins. They are relatively similar looking, at least until you get up close and notice the different shades of black as well as the finishes applied. The corners have oval cutouts angled in the metal frame which acts as a mounting bracket too. Three of the four sides are plain, and then we get to the fourth side where we get Granzon branding in an acrylic badge, as well as cutouts in the POM through which we can access a micro-USB and full-size HDMI port. The opening is quite large to accommodate the cables, which does mean the block looks somewhat DIY—especially with the PCB also visible here. It must also be noted then that this CPU block, which is meant to be part of a watercooling loop, is ironically not waterproof itself. The cables fit in easily, and you will have to connect the USB cable to a spare port for power, and then the HDMI connector goes to your GPU or motherboard video out. Now how exactly you would get these cables out of the case and to the back is up to you, Granzon certainly does not provide a PCIe slot cover meant for these to pass through! It's one more way that I feel Granzon didn't really plan things through fully.


Turning the block around, we see a protective sticker placed over the nickel-plated copper cold plate. There is no pre-applied thermal paste akin to Bykski, but Granzon should have included a thermal paste tube to try and at least distinguish itself from the more affordable parent brand. The cold plate is rectangular to match the block itself, although the actual contact area here is square as typical of an Intel CPU block. This section has a slight convex shape to it which flattens out during installation courtesy applied pressure at the corners. It is machined well although not polished as with a few other blocks we have seen before—this does not matter for the actual performance of the block either way.


Disassembly was done after testing was completed and involves the removal of the six 2.5 mm socket head screws securing the cold plate—keep in mind that one of them has a telltale sticker on top which will show you have disassembled the block, and doing so may end up voiding warranty. The funny thing is one of the wrenches provided by Granzon works for the stop plugs on the side, but the other one doesn't fit anything, including the mounting posts. I can only wonder if the wrong size was included here. The two main parts of the block—the top with the integrated mounting bracket and the cold plate—are now fully separated for closer examination. We can also now remove the triangular jetplate which has a similarly shaped O-ring underneath, in addition to a larger one around the entire cooling engine to ensure the coolant flows only where it should. The stainless steel jetplate is 0.5 mm thick and the cold plate itself is thicker than average at 5.5 mm in the middle and 2.5 mm outside. The fins are ~3 mm tall, occupy an area of 38 x 34.9 mm, and are 220 µm thick with a 200 µm spacing between them for the coolant to flow through the microchannels. This is a step up from the previous Granzon block in terms of the fins now occupying more space to slightly increase the active heat transfer surface area, but the cooling engine itself is relatively simple compared to some of the competition today. In fact, it's the exact same cold plate as what we saw on the Bykski CPU-FIRE-ON-I block earlier, so this feels like more brand mixing than really justified if the top is the only difference. Sure, that can also affect the cooling performance and flow restriction, but I expect to see this Granzon GAISC to not be that far off from the Bykski CPU-FIRE-ON-I in either metric.