Assessing the cooling performance of the Arc Mini R2 is difficult since we only have one comparable result with the new graphics card. However, the CPU and overclock settings we use have remained unchanged for some time, and looking back through previous reviews reveals that although the Arc Mini R2 at full speed can't match the SilverStone Sugo SG10 at its lowest speed, its delta T here of 44°C is still among the best, with other cases having reached the high 50s. The SG10's use of an Air Penetrator fan right above the CPU cooler is what gives it such a big advantage here.
Removing the HDD cage to improve airflow from the front intake does nothing to improve the CPU temperature at high speed, so once again we see that the exhaust fans are more important here. Dropping these to their medium and low speeds sees temperatures climb by 4°C and then a further 3°C, with the medium (7V) setting proving to be best compromise between noise and performance. That said, even at high speed, the Silent Series R2 fans could hardly be described as loud, although you will hear them.
Click to enlarge - It's not too difficult to keep the Arc Mini R2 tidy
The Arc Mini R2 also does well to keep its GPU temperatures at least close to those of the SG10, which positions the GPU against its side vents such that it has a supply of cool air that's essentially unimpeded, which is why its temperature barely improves at the SG10's maximum speed. As for the Arc Mini R2, its GPU temperature sees improvement when you remove the top HDD drive cage, emphasising the benefit of the front intake fan and front mesh. As you lower the fan speed, temperatures climb, although no more than expected. At minimum speed, the fans are nearly silent, but you won't see much (if any) air reaching the GPU, especially with that drive cage installed, so we'd again opt for medium speed as the best compromise.
In moving the Arc Mini to the R2 revision, Fractal has left much of the core design unchanged, but that's a good thing as it was already great to start with. A few modernisations like bringing more USB 3.0 ports and fan control to the front panel are overtly sensible choices. Elsewhere, the window makes sense given that this is clearly a case made for water-cooling, although we'll leave the issue of how well the tint works up to you.
Click to enlarge
The question of 'which micro-ATX case?' is best answered by another question, and that's whether you're going to be relying on air or water to cool your hardware. If it's the former, SilverStone remains top of the pile. Its SG10 is expensive but fantastically crafted and almost unbelievably small, while the ever awesome TJ08-E crams heaps of performance into a tidy and good value package, and both cases also feature tasty aluminium front panels.
As for water-cooling, we'd previously have recommended the Corsair Obsidian 350D, as nothing else really came close. However, the Arc Mini R2 changes that somewhat – not only does it offer more flexibility for water-coolers, but it does so for a price that's £25 less, which is significant cash in the case market. Both cases are certainly large for micro-ATX enclosures (Fractal's is shorter but Corsair's is shallower), but that's to be expected when water-cooling, and the Arc Mini R2 certainly doesn't waste the space that it occupies. The fact that it also includes fan control where Corsair doesn't and has more storage options as well means the decision between the two is an easy one.