Review Raijintek Leto W Cpu Cooler

Times are interesting, when you are in the market looking for the perfect cooler for your new CPU and you are presented with hundreds of options, from the cheapest to the most expensive. The more you look, though, you may sometimes find yourself just in the middle of a forest of offers and technical data that just are too confusing and you wish that things could be more simple. Enter the Raijintek Leto W CPU Cooler. Let’s see with the present review if this new CPU cooler will make your life more simple…

Raijintek LETO Cpu Cooler

Packaging and Content

The packaging of the Raijintek Leto W (“W” stands for White) is colorful enough to attract your attention when sitting on the shelf at that computer shop you go to to find new IT hardware, but not flashy at all: the dark grey color is predominant, and pictures of theproduct from various angles can be found on every side.

Raijintek Leto W CPU Cooler – package front

Raijintek Leto W CPU Cooler – package side

Raijintek Leto W CPU Cooler – package side

Technical details are to be found on the back side of the rectangular box, as is to be expected. Nothing new.

Raijintek Leto W CPU Cooler – package rear

The contents of the box are also standard for a modern CPU cooler: apart the coler itself and the accompaining fan (more on this paticular fan later) you will find a booklet for the installation instructions, in several languages, and the installation gear.

Raijintek Leto W CPU Cooler – accessories

A Closer Look – The Cooler Heatsink

The form factor of the cooling tower is also noting extraordinary: we have 3x 8mm heatpipes, painted in a special thermal paint that gives them a shiny black surface color (this is something Raijintek has done in the past as well with high end cooling products) in “U” shape, going through a series of aluminum fins, also nicke plated in shiny black, that are well spaced between them and thin enough to speed up heat dissipation, even with low airflow. The design of the fins is a bit odd, but similar to other Raijintek products: the fins have a wave shape in the middle of their edge, making the profile of the tower cooler not exactly symmetrical if looked at it directly from the front. I have no idea if this is just a design choice, or a more thoughtout way to increase dissipation surface. I guess the first is the case, since I don’t see it dissipating that much of heat from the thin borders anyway.

Raijintek Leto W CPU Cooler – heatsink tower

The U-shaped heatpipes are conneted together to a quite large and heavy chunkof aluminum block at the very base of the cooler: This block acts as a bonding agent for the heatpipes and surface contact area for the CPU heatspreader. The heatpipes are visible from the base, which has milled down to just make sure the heatpipes are directly touching the CPU for better heat dissipation. Raijintek calls this CPU Direct Contact (or CDC) and we have seen this “trick” used on almost 90% of CPU coolers (and even VGA coolers) in the past 5 years or so. Raijintek gains some points here, since there is virtually no gap inbetween the heatpipes and the aluminum block, maximizing contact area. Well done.

Raijintek Leto W CPU Cooler – heatsink base

Raijintek Leto W CPU Cooler – heatsink sticker

Raijintek Leto W CPU Cooler – heatpipes

Raijintek Leto W CPU Cooler – heatpipes detail

A Closer Look – The Fan

If the heatsink body was quite standard in design and functionality, I cannot say the same for the included fan. This is something Raijintek presented first only as an add-on for their coolers at Computex 2017, starting to offer it only more recently as a stand alone product, probably responding to customer requests. It is a very cool (pun not intended….) fan, after all!

Raijintek Leto W CPU Cooler – fan structure

Lets see how this fan is made of: first of all, the blades are translucent. Nothing really new, I have seen fans with transparent blades before. But the blades on this particular fan are, again, translucent: this means they are not perfectly transparent, but hage a foggy – sand blasted appearance that diffuses light when shone through them. The central hub, though, is a black plastic cap with the Raijintek logo sticker glued to it. It covers the electronics and the bright light LEDs that provide the illumination on this fan, so the light comes out from the center outwards through the blades, instead of the more traditional pattern from tthe outer fram inwards against the blades. This guarantees a more uniform brightness and illumination of all the blades, and avoids those 4 curved light beams you usually see on low budget fans with LEDs.

Raijintek Leto W CPU Cooler – fan

Raijintek Leto W CPU Cooler – fan hub

The frame of the fan is what really makes this product literally shine: the outer plastic frame has a weird conical shape on the 4 angles, where the installation holes are. No pass-through long screws are needed to install the fan, you will have to use the included rubber pins. The frame is also made of two parts: the outer black frame, and an inner frame, in again translucent plastic material, although a bit more foggy than the blades. This reflects the light from the LEDs in the central hub back to the blades, completing the uniformity of the lighting effect.

Raijintek Leto W CPU Cooler – base

Raijintek Leto W CPU Cooler – fan corner

Raijintek Leto W CPU Cooler – fan corner

Installation

Installing the Raijintek Leto W CPU Cooler is simple, but requires some planning. You won’t be able to install it on the CPU right out of the box. You need first to remove the motherboard from the case, since this cooler comes with its own backplate. AMD users will have to completely remove the AMD AM3 and AM4 preinstalled installation mechanism to be able to use the LETO, while INTEL need only to apply the back plate to the motherboard.

Once you have installed the mounting system of the cpu coler to the motherboard, following the excellent instructions found on the booklet, remove the protective ssticker from the base of the LETO and place it on top of the CPU heatspreader, after having applied some thermal paste. Use the bracket to screw it down firmly in place, and you are basically done. Apply the fan, passing the rubber pins through the mounting holes, connect the 4-pin fan header to the CPU fan header on the moderboard, and if you didn’t mess these simple steps, you can turn on your PC. Simple, right?

Noise and Acoustics

Considering that we do not have a professional setup (not yet) to measure sound and noise levels, it is pretty hard to talk about something that can be said to be perceived differently from person to person. My personal perception of noise may be different from another person’s perception: what I consider as “loud” can be consider as a whisper by somebody else, so it is a very subjective argument to talk about without proper measuring tools.

Even with tools, the same subjectiveness applies, but at least we get numbers we can compare throughout different products. We will get to that in the future. Untill then, we will have to go on witth our “hear” as a measuring device, so you all need to ttake all the following considerations as strictly personal and non-conclusive.

Having clearified that this particular part of the review is to be taken with a grain of salt, I can honestly say that the fan that comes with the Raijintek Leto W CPU Cooler is not the loudest I have heard, but also not certainly the quietest. The fan is PWM controlled, so the BIOS of the motherboard handles the RPMs according to the temperature of the CPU. The RPM range goes from 800 to 1800, with a max Air Flow of 67 CFM and 1.2mmH²O Air Pressure value. These figures are declared from the manufacturer, of course, but based on my experience, both air pressure and air flow should not differ that much from reality. We never believe to 100% the values declared from manufacturers for fans, since I have personally seen in the past that these can differ up to 25% from reality, and up to 10% from fan to fan (same manufacturer and model of fans), but in this particular case we are comfortable to say that, even if probably not 100% spot on, the values declared differ from reality way below those average percentages. When we finally get our hands on proper measuring tools, all fans will be tested again, and we’ll see if the initial personal impressions are reflected in the instrumental test results.

Performance Test Results

If noise was hard to test and to write about, due to the lack of proper measuring tools, the cooling performance of the RAijintek Leto W CPU Cooler is way easier to measure, since the motherboard itself is the actual tool, with its embedded temperature sensors on the PCB and the capacity to read core temperatures in the CPU as well. You just need a good software, and we tend to use several different ones and average their values, just to be sure. Speaking of software, we use CoreTemp and SpeedFan, as well as HWInfo to measure the temperatures of the CPU. Which brings me to talk about the methodology

Testing Methodology

We are not using a normal case to test CPU and VGA coolers, but we are installing all the components inside the new Lian Li PC-70X Bench Table we reviewed some time ago. This specifically built platform (a bench table is nothing else than a case stripped down to the essentials and alloweing ewasier access to hardware) allows us to perform open and enclosed air tests, so to a variety of scenarios, including the possibility to increase and / or decrease the ventilation options, actually testing which cooling solution works the best for any given CPU and GPU cooler.

We disable all the motherboard’s CPU fan control and power management features, while the CPU heatsink fan is powered at 12V, 7V and 5V (in the case of liquid cooling with multiple fan radiators, the same applies for all fans). Only the average values are then taken into consideration and noted down. The system is then loaded using for the CPU Prime95 (using the latest version available). CPU temperatures are read using the latest version of CoreTemp. All values are taken when temps are stabilized, no matter how much time it takes (usually some 15 – 20 minutes are enough). Additionally, case temperatures are taken in several spots and averaged, using a thermocouple. This also includes exhaust temperatures of case fans at approx. 5cm from the bench table when closed.

Test System

I decided to install a basic system I am using for testing purposes and that includes the following components:

• AMD FX-8350 4GHz Black Edition
• AsRock 970 Pro3
• Radeon HD 6950
• Antec True Power Quattro – 1000W
• 2,5″ Notebook Hard Disk

The test system may seem outdated to some, but it still packs some punch, specifically if we consider the amount of watts the CPU puts out: the TDP is 125W so it will definitively be able to stress the cooler to its limits. To avoid direct comparison with more modern CPUs, which honestly would not make sense, I decided not to perform any overclock on the CPU. This decision is based on the fact that the cooler is not really targeted to overclocking enthusiasts anyway, but rather to gamers or modders that are on a budget but still want performance and looks – more on this at the end of the review.

Raijintek Leto W CPU Cooler – system installed

On a side note: the test system will be soon updated, so stay tuned for an update on this same review with the new hardware.

Test Results – Closed Bench Table

As we mentioned earlier, the Lian Li PC-70X Bench Table allows us to actually test 2 separate scenarios: a closed and an open air system. First off, we will analyze the closed system scenario, since it is the one most people will relate to due to their systems being enclosed inside cases.

The chart depicts well the situation we face when installing a high power system inside a well ventilated case. Although the system does function perfectly well, and the ventilation is optimal, the Raijintek LETO W CPU Cooler actually struggles a bit to cope witth the power output of the AMD FX-8350 Black Edition at the stock frequency of 4GHz under stress. The highest temperature value of 75°C was reached fairly quickly and didn’t go beyond since the CPU started thermal throttling, basically reducing the multiplier from 20x to 7x thus reducing the frequency down to 1400MHz. No matter what I tried in BIOS, the thermal throttling just kicked off at 75°C precisely. It is clear this CPU is way too much for this cooler to handle.

Test Results – Open Bench Table

The situation with the open bench table did get a bit better if we consider all values (case temp, motherboard temp, GPU temp and CPU Temp) at idle, as it would be obvious to expect. Yet I find myself again hitting the thermal throttling barrier when stressing the CPU.

As you can see, the highest temperature unders stress is also 75°C, but only because the CPU trottles thermally at such temperature. The only difference is the speed att which the CPU reaches said limit: in thhe open case scenario the temperature rises a bit slower than in the closed case scenario, meaning that the ventilation system in the latter case is actually not as effective as with the bench table completely open and exposed to ambient temperature.

Conclusion

We can only speculate why this is so: the Raijintek LETO W Cpu Cooler is mounted, on our test system, with the fan facing towards the GPU. In a normal system inside a vertical case, this means that the fan blosw air from the area right above the GPU, through the fins and towards the top of the case. Since the fan itself allows only one way for it to be installed, due to the oddly cone-shaped frame with installation holes only on ones side, the cooler works in what is usually called a “push” configuration. The alternative “pull” configuration is, with this particaular fan, not possible. Furthermore, the socket orientation itself forces the cooler to be mounted so that the fan blows upwards: the rear case fan cannott really help much in removing the hot air from the case in this particular configuration.

Raijintek Leto W CPU Cooler – system built

An additional consideration can be made, but this is specific to the motherbboard used for the test: the mosfets are surrounding the socket and are all placed towards the I/O ports of it. TThe CPU Fan should move the hot air from these components if it were installed blowing toward the back of the case. This particular situation causes the mosfets to get very hot under stress, causing of course the thermal throttling we noticed with both the open and closed case scenarios.

All this considered, do keep in mind this CPU cooler is not really meant to be used on so old CPUs, but instead on the new AMD Ryzen and Intel Core i3 / i5 / i7 CPUs which are installed on motherboards that benefit from a better mosfet design and displacement. The Raijintek LETO W Cpu cooler did do a good job nevertheless, being able to effectively cool down such a powerful CPU in all normal usage situations, even if under stress with Prime95 it was not able to avoid that the CPU hit its thermal throttling limits. This is. though the worst case scenario that should not be the average usage for the customer this cooler is targeted to: light gamers and modders that are on a budget. In fact, for the price it is sold, it is a pretty good product: you can buy it on Caseking.de for € 29,90, which is actually a bargain.

I decided to award the Raijintek LETO W CPU Cooler our Gold award.

For under 30€ + shipping, this is a great product even if it really could not handle the 125W my CPU outputs and the fan only allows one way to mount it.

Thanks to Caseking and Raijintek for providing the sample for this review.

You can find this and other Raijintek products also on Amazon.de: