The Dark Rock 4 and Dark Rock Pro 4 CPU air coolers by be quiet! are the 4th in line to carry that specific name right after the highly successful Dark Rock 3 and Dark Rock Pro 3 models released back in 2014. As a matter of fact both the 3 and 4 models are very similar (both in terms of design and size) so if we had to guess it would seem that be quiet! took the former line back to the drawing board further tweaked it and released it again. Strangely enough although the Dark Rock 4 shares almost the exact same measurements as its predecessor (159x136x96mm vs 160x137x97mm) and is actually lighter (920g vs 976g) it features a higher TDP (thermal design power) of 200W (as opposed to 190W of its predecessor). The same applies for the Dark Rock Pro 4 but this time over although it's also roughly as large (163x136x146mm vs 163x137x150mm) and as heavy (1130g vs 1197g) as it predecessor they both feature a TDP of 250W. The similarities however don't end there since both the Dark Rock 3 and 4 feature the same number of fins (51) and heatpipes (six 6mm ones) and of course the same is true for the Dark Rock Pro 3 and 4 models (90 fins - 45 on each of the two heatsinks - and seven 6mm heatpipes). The same wave contour fin design was also used in the new Dark Rock 4 and Dark Rock Pro 4 models (just like with their predecessors) along with similar brushed aluminum diamond cut top covers (we like the new ones better). The same 120mm PWM SilentWings fan was also used both in the Dark Rock 3 and 4 models (1400RPM/67.8 CFM/20.8dBA). So what did be quiet! change in the new Dark Rock 4 and Dark Rock Pro 4 models? Well for one they used a nice looking black coating which according to them thanks to its ceramic particles helps with heat transfer (even if it doesn't however it still looks great). We were also surprised to see that be quiet! used different SilentWings fans for the Dark Rock Pro 4 and to be more specific although the Dark Rock Pro 3 came with a 120mm (1700RPM/57.2CFM/21.5dBA) and a 135mm one (1400RPM/67.8 CFM/20.8dBA - same as the Dark Rock 3/4) the Dark Rock Pro 4 comes with two slower 120mm (1500RPM/50.5CFM/18.9dBA) and 135mm (1200RPM - no other data is available at this time but we expect a CFM placed at just over 60 with just below 19dBA of noise).