Thermalright TL-C12C fan: Also works in reverse

So, we have results for a Thermalright fan. While the first attempt (or second, if we count the now-discontinued model X-Silent 120) didn’t quite hit the mark, it’s probably fair to say that this is a more attractive option than the Scythe Kaze Flex II 120. Yes, these two fans are being directly compared because they share an unusual trait – they spin in the “reverse” direction, from left to right. And as you know, most fans spin the other way…

Let’s first look at why it even matters which direction a fan spins. We’re talking about how air is broken up during movement, assuming the airflow direction remains the same. In an isolated environment, this shouldn’t matter theoretically – what determines performance is aerodynamic design (the shape of the individual blades, the relationship between blade shape and the frame, and so on). But there’s still a valid reason to examine this issue – especially in the context of heatsinks or radiators with at least two fans operating in series.

That means one fan (pushing air through the heatsink fins) feeds its streamlines into the second. In such a configuration, streamline separation behind the heatsink is reduced, which minimizes the negative impact of centrifugal forces and helps maintain higher pressure between the fins – improving cooling performance. This is the theory Scythe introduced with its Fuma series of coolers, though Thermalright seems to approach things differently. In fact, Thermalright’s multi-fan coolers tend to use all either clockwise-rotating or counter-clockwise-rotating fans.

If we haven’t missed anything, Thermalright doesn’t seem to prefer mixing impeller spin directions in its CPU coolers. Apart from Scythe (and its Fuma 3, for example), graphics card manufacturers also use such mixed setups – in triple-fan designs, the center fan often spins in the opposite direction, which naturally makes the most sense. In any case, this is mostly cosmetic, and whether higher cooling performance is achieved at comparable noise levels depends on many factors. You’ll likely remember that the Fuma 3 cooler wasn’t particularly outstanding in terms of cooling efficiency. The use of counter-rotating fans may have a positive effect, but clearly it’s not enough to outperform competing solutions.

And now to the Thermalright TL-C12C fan. The impeller spins clockwise, and the blade geometry is adapted accordingly. The leading edges of the blades are on the right side, unlike the majority of fans (which have the traditional counter-clockwise rotation). Regarding the aerodynamic design, there is an evident effort to keep the blades short enough to reduce flex while minimizing the gaps between them, which helps maintain good static pressure.

The number of blades is average – there are nine. Their angle is relatively shallow, similar to that of the Kaze Flex II 120, but the individual blades on the Thermalright fan are more robust and wider, which makes sense given the lower blade count (9 vs. 11). Still, we’re entering testing with the assumption that this fan design is aimed primarily at achieving high airflow (with weaker static pressure). This is supported by the specifications listed by the manufacturer for the TL-C12C.

  

It’s also important to understand that the Thermalright TL-C12C is a budget-friendly option. Three-packs are commonly available for around €15, and individual units go for under seven euros. That’s comparable to (and sometimes cheaper than) the price of Arctic P12 fans. So, we’re not looking at uncompromising high-end fans, but rather an affordable, low-cost solution that remains accessible even if you need several units.

The maximum speed of the 120 mm TL-C12C fans is around 1550 RPM, placing them in the “quiet” or more accurately “moderately quiet” (or moderately loud? – take your pick…) category.

The fan cable has two connectors. One is for connecting to the motherboard (or a fan hub), and the other is for daisy-chaining another fan. The benefit of this design lies in cleaner cable management, where multiple fans can be connected in series and only one cable leads to the fan header that powers and controls them. Unlike other fans, the TL-C12C comes with a relatively long cable (46–53 cm), which can be either an advantage or a disadvantage depending on your setup (e.g., if long cables get in the way). In any case, this is likely because no extension adapter is included, and Thermalright seems to have wanted to ensure the cable is long enough for any situation.

Please note: The article continues in the following chapters.