Can a mid-height downdraft cooler keep up with our overclocked Haswell-E CPU? We put the Dark Rock TF by be quiet! through our tests to find out.
The two major advantages of downdraft CPU coolers is that they don’t need to be as tall as cross-flow coolers, and they blow more air across a motherboard’s voltage regulator. To us, that sounds like a single design solution for two potential system configuration problems. Disadvantages include an increased amount of air re-circulation and reduced directional velocity at the cooler’s exit, due to the motherboard being in the flow path.
But wait, did I just say downdraft and cross-flow? The firm be quiet! is ready to set me straight, naming its downdraft cooler the Dark Rock TF for top flow. While I’d probably say downdraft and "cross-draft" were I looking for some level of naming consistency, a rose by any other name really does smell as sweet.
The Dark Rock TF differs from most similar designs in that it has two radiators and two equally-sized fans. The smaller lower radiator is narrow enough to fit beside memory modules, which themselves can stand up to 1.9” tall beneath the fan. This design pushes overall height of the cooler to 5.1” with the top fan. If that sounds too tall for your case or too short for your RAM, it’s also possible to leave one of these fans out. However, doing so reduces the Dark Rock TF's cooling performance.
The Dark Rock TF includes a universal support plate for Intel square ILM (775 to 1366) and AMD rectangular-pattern mounting holes, a set of standoffs for LGA 2011 (-v3) integrated support plates, separate Intel and AMD mounting brackets, a fan cable splitter, thermal paste and a special wrench. You’ll need the wrench for LGA 2011, and AMD users will need to remove their clip-on-cooler bracket to gain access to their motherboard’s mounting holes.
Rated at 1400 RPM, both 135mm fans have 120mm hole-spacing to ease replacement with standard parts.
The Dark Rock TF’s base is smooth, but not polished. Finely-machined surfaces often do a great job of keeping thermal paste in place, but without requiring much of it.
The be quiet! installation kit uses standard screws, rather than locked-in studs, for its support plate. A pair of nuts hold threaded spacers to the top bracket, while black clips above the motherboard hold those screws in position with the support plate behind the motherboard. That makes installation on most processors as easy as attaching the chrome parts to the heat sink, adding the black parts to motherboard, and screwing the chrome parts onto the black parts from behind the board.
LGA 2011 (v3) installations are more complicated, since some of those boards don’t have holes for screws. Instead, the be quiet! installation kit includes special standoffs to use the motherboard's integrated cooler bracket. Those go on the board first, then the cooler's brackets go onto its base, and nuts attach the cooler's bracket to standoffs by reaching between the motherboard and cooler. The special wrench is designed to reach under the cooler body as well, and this entire operation requires everything nearby, such as DRAM, to be removed.
We typically use downdraft coolers when there’s too little space inside a case for a cross-flow model, expecting that we’ll need to give up some cooling performance for the sake of space. Entering this test with a full understanding of why the Dark Rock TF wouldn’t perform as well as its upright competitors, we’re still very pleased to see that it passes the test with our overclocked Haswell-E CPU.