Graphics Card Armor: Thermalright T-Rad2 GTX Cooler and VRM Heatsinks

Today we are going to talk not just about a graphics card cooler, but about an entire kit for fully-fledged and highly efficient cooling for extremely hot graphics accelerators.

by Sergey Lepilov
10/12/2009 | 03:23 PM

As you know, graphics cards become more powerful year after year. In ever-lasting hunt for extra FPS the manufacturer not only constantly improve the graphics processors, but also increase the PCB design complexity making often as many as six or even seven phases in the graphics card voltage regulator circuitry. Of course, it increases the requirements to graphics card cooling systems that is why they are not longer just a heatsink with a fan, but acquire additional functionality. Things are much simpler when it comes to mainboard voltage regulator components, because most of them are provided with additional heatsinks with heatpipes by the manufacturer right from the start. However, as for the graphics cards, it is much more complicated to offer an alternative efficient VRM (Voltage Regulator Module) cooling, because the cards have much smaller PCBs that are overloaded with electronic components.


Most manufacturers of cooling solutions for graphics cards prefer not to address this matter at all releasing coolers that only cooler the GPU and send some airflow towards the PCB at best. However, this is absolutely not enough, and a great example here is the recently reviewed Arctic Cooling Accelero Xtreme GTX 280, which cools the GPU perfectly fine, but does nothing to improve the thermal mode of the PCB VRM components. But it is very pleasing to see that some manufacturers acknowledge the need for proper VRM cooling. One of these companies is Thermalright Inc. that has recently released an updated version of Thermalright T-Rad2 GTX and two heatsinks for the VRM components of ATI Radeon HD 4870/4890 graphics accelerators. Our today’s article will talk about these particular solutions.

Thermalright T-Rad2 GTX Cooler

Relatively small flat box is designed following Thermalright’s best traditions: brown cardboard with the company name on the top cover…

… and the cooler model name on one of the sides:

The distinguishing feature of all Thermalright packaging is minimum information on maximally modest packaging. Some users believe that this is the way packaging should be designed, as serious solutions should ship in serious boxes. Some believe that these boxes won’t be well noticed on the store shelves because they are way too simple. Both these points of view have the right to exist, although in my opinion, the most important feature of the packaging should be its ability to protect the device inside properly, and Thermalright has no issues here, because the cooler sits inside tight polyurethane foam casing covered with a sheet of the case material.

Thermalright T-Rad2 GTX is bundled with a bunch of useless aluminum heatsinks, a set of screws, washers and bushes, Thermalright The Chill Factor thermal compound, installation manual and a sticker with the manufacturer’s logo.

There are no fans included with the cooler. This solution is made in Taiwan and its recommended price is $56.95.

Thermalright T-Rad2 GTX has very brutal looks and in my opinion resembles a piece of some futuristic armor more than a cooler heatsink:

It is pretty heavy for its size – 360 g with 228 x 105 x 25 mm dimensions:

Thermalright T-Rad2 GTX consists of six copper nickel-plated heatpipes 6 mm in diameter that come out of the copper nickel-plated base and pierce aluminum heatsink plates:

There is an aluminum panel attached with screws to two side plates on the front of the heatsink that serves as the base for the fans.

One heatpipe goes through the lower part of the heatsink, while the other five – through the upper part:

The heatsink array consists of 85 aluminum plates. Each is 0.35-0.4 mm thin and the space between the plates is a little less than 2.0 mm.


The heatpipes lie in special grooves in the copper cooler base and are soldered to them. The thickest part of the base plate below the heatpipes is no bigger than 2 mm:


They use soldering technique not only where the heatpipes contact the base, but also where the heatpipes contact the heatsink plates. As you can see, it is not always done neatly enough:

As usual, the copper nickel-plated heatsink base of Thermalright T-Rad2 GTX is bent, namely it has a bump in the center:

Despite this fact, the thermal compound imprint from the ATI Radeon HD 4890 graphics processor is very solid, while the one from Nvidia GeForce GTX 275 unfortunately, not quite:


In conclusion to our overview of the Thermalright T-Rad2 GTX cooler I have to add that this heatsink can accommodate two 92x92x25 mm fans or one 120x120x25(38) mm fan. We are going to discuss their installation procedure as well as graphics cards compatibility in the corresponding chapter of our review.

Thermalright VRM1 and VRM2 Heatsinks

There are no VRM heatsinks for Radeon HD 4870 and HD 4890 included with Thermalright T-Rad2 GTX cooler and in my opinion, it is the best solution. Let me explain why. First, by adding any of the VRM heatsinks to T-Rad2 GTX accessories bundle, they would inevitably increase its already pretty high price and hence made this cooler less appealing to the end-user. Who knows, maybe you would like to use some other VRM heatsinks or prefer to cook breakfast on it and so you don’t need any extra heatsinks at all. Second, Thermalright designed VRM heatsinks of two different types: VRM1 and VRM2 that differ by the positioning of the side-mounted heatsink. In other words, it is up to the user to decide what particular VRM heatsink will suit best for his particular system case, which is quite logical.

So, VRM heatsinks are shipped in boxes of the same design as T-Rad2 GTX, only smaller:

The side sticker indicates the heatsink model. Besides, the boxes are of different height, so you won’t mix up the two heatsinks:


The heatsinks are bundled with two thermal pads, two wire clips for an 80 mm fan and an installation instructions sheet:

The heatsinks are both made in Taiwan and are selling at $28.95 for VRM1 and $29.95 for VRM2.

The only difference between the two is the direction in which the side-mounted heatsink is turned: when you install VRM1 onto the graphics card its side-mounted heatsink will be parallel to the mainboard, while by VRM2 it will be perpendicular to the mainboard:


The schematic layouts below show the detailed dimensions of the heatsinks:


Other than that the two heatsinks are identical and consist of a heat-spreader, heatsink and two copper nickel-plated heatpipes 6 mm in diameter connecting them together:

Each VRM heatsink weighs about 160 g total. The side-mounted heatsink consists of 25 aluminum plates, each perforates with 12 rectangular holes and 4 triangle ones.

Each plate is 0.45-0.5 mm thick and the gap between the plates is about 2mm.

You can use two wire clips included with the heatsink to mount an 80x80x25 mm fan, but our test results showed that you don’t really have to do it at all.

The heatpipes are soldered to the heatsink base, as you can tell from the traces of soldering on the heatpipes:

There are thermal pads included with the bundled accessories, but according to the instructions, you will only use one during cooler installation. It must be applied between the VRM and the heatsink base:

Thermalright TR-SL-92-1500 Fans

Another component that wasn’t included with Thermalright T-Rad2 GTX, but is necessary for effective cooling is the 92x92x25 mm fans. Thermalright offers them too, although at this point in limited quantities. And here I could disagree with the manufacturer, because I personally do not feel like spending time looking for two high-quality 92 mm fans, so it would be nice to have them as part of the bundled accessories. Especially since they fit T-Rad2 GTX perfectly and cost very little – only $3.50.

I am talking about Thermalright TR-SL-92-1500 fans that ship in small boxes with a clear plastic window in front:

Glossy black frame and semi-transparent fan blades in the color of honey make the fans look very attractive:

The fan rotates with constant speed of 1500 RPM and creates 26.78 CFM airflow.


According to the official specifications, the level of generated noise shouldn’t exceed 24.6 dBA. Subjectively, Thermalright TR-SL-92-1500 fans work surprisingly quietly at 1530 RPM (according to the monitoring data), and at 1000 RPM they become completely noiseless. They owe this extremely quiet operation to a slide bearing with 20,000 hours declared MTBF (at 25 °C temperature):

The fan’s maximum power consumption doesn’t exceed 2.64 W at 0.22 A current. Each fan weighs 85 g, so with two fans installed Thermalright T-Rad2 GTX will get another 170 g added to its 360 g.

Graphics Card Installation Tips

Thermalright T-Rad2 GTX is compatible with NVIDIA GeForce GTX 260/275/280/285 and ATI Radeon HD 4870/4890 grap0hics cards. In fact, you can try and install this cooler on some other graphics cards, too, if you measure the distance between the retention holes carefully. T-Rad2 GTX has 53 mm between the retention holes on the inner perimeter and 63 mm between the retention holes on the outer perimeter. At this point, the compatibility is still a question, because of the heatpipes coming out of the cooler base and twisted in a pretty sophisticated manner, as they can interfere with the graphics card connector panel. In this case you have to take into account the distance from the center of the heatsink base to the end of the cooler side with the heatpipes: 83 mm. In other words, if the distance between the GPU center and the connector bracket is bigger than 83 mm on your graphics card, then you may be able to install Thermalright T-Rad2 GTX onto your graphics accelerator.

I am going to talk about the installation procedure using Radeon HD 4890 1 MB graphics card as an example. First, you have to remove the reference cooling system and wipe off the thermal interface and the remainder of the thermal pads from the GPU and graphics card VRM:


After that you have to install the VRM heatsink. First you remove the protective film and stick the enclosed thermal pad, then fasten the heatsink on the graphics card with two screws and two plastic washers:


This is what Thermalright VRM2 heatsink looks like on Radeon HD 4890:

Thermalright T-Rad2 GTX also installs very simply and intuitively. You have to insert the mounting spindles into the loops of the retention frame, put the graphics card over the cooler and tighten large screw-nuts with rubber washers beneath them:


In the end the “armored” graphics card looks really beautiful, and with two 92 mm fans – even better:


This is what Radeon HD 4890 with installed Thermalright T-Rad2 GTX and VRM2 looks like inside the system case:


As you can see, with a tower cooler inside, it makes more sense to use a second modification of the VRM heatsink, as it will provide higher cooling efficiency. Although Thermalright VRM1/2 won’t be compatible with any tower cooler (for example, you won’t be able to install IFX-14). Therefore, I would like to provide you with the measured distance from the graphics card connector bracket to the side of the heatsink: 178 mm. I have to add that when you install Thermalright T-Rad2 GTX with fans, two PCI slots next to the graphics card will be blocked.

Instead of two 92 mm fans, you can equip Thermalright T-Rad2 GTX with a single 120 mm fan using two wire clips included with the cooler:

Here let me tell you that a single 120 mm fan is not as efficient in terms of cooling as two 92 mm fans.

Thermalright T-Rad2 GTX can be installed onto graphics cards based on Nvidia GPUs, such as GeForce GTX 260/275/280/285. This is what a graphics card like that will look like with this cooler on it:


At this time Thermalright doesn’t offer any VRM heatsinks for these graphics accelerators and when I asked a company representative about the possible ETA for these solutions, I got no definite answer.

Another issue with T-Rad2 installation onto GeForce graphics cards is the absence of a special heatsink for the NVIO chip. In fact, there is a heatsink among the bundled accessories, however, it simply doesn’t fit beneath the heatpipes hanging over the chip:

I even tried to stick a small aluminum heatsink intended for the memory chips onto the NVIO, but the glue wasn’t sticky enough to securely hold the heatsink in place.

I have to admit that even though Thermalright T-Rad2 GTX solution is compatible with Nvidia graphics cards, unfortunately, you won’t be able to create proper cooling for all thermally challenging PCB areas.

Testbed and Methods

We tested the new cooling system from Thermalright inside a closed system case. Our testbed was identical for all coolers throughout the test session and featured the following configuration:

To increase the total system heat dissipation and make it the testing conditions a little harder for the participating cooling solutions we overclocked our quad-core processor to 3.93 GHz (+47.2%) and increased its Vcore to 1.35 V (+12.5%) in the mainboard BIOS.

The memory voltage was at 1.62 V and its frequency was 1500 MHz (7-7-7-14_1T timings).

The testing programs were installed under Windows 7 RTM x64. We used DirectX libraries (from March 2009) and Catalyst 9.8 and GeForce 190.62 graphics card drivers. We used 10 runs of FireFly Forest test from the synthetic 3DMark 2006 suite in 1920x1200 resolution to warm up the graphics cards. We enabled full-screen antialiasing 4x and anisotropic filtering 16x:

Besides, we additionally used FurMark version 1.7.0 stability test that was launched for about 10 minutes in 1280x1024 resolution:

We used RivaTuner v2.24 (created by A. Nikolaichuk aka Unwinder) to monitor the frequencies and temperatures of our cards.

The tests were run at least twice for each tested cooling system. The temperature stabilization period between the two test cycles was about 10-12 minutes. The ambient temperature was checked next to the system case or open testbed with an electronic thermometer with 0.1°C precision that allows monitoring the temperature changes over the past 6 hours. During our test session room temperature stayed around 23.1-23.5°C.

Let’s take a look at the graphics cards, their cooling systems and specifications: 

Why did we test our cooling solution GeForce GTX 260 and GTX 275 with pretty similar characteristics? First, because they have different stock coolers (and different PCB layouts). And second, because GeForce GTX 275 that we tested first has no diodes for monitoring the temperatures of VRM components, which are just as important as the GPU temperatures. GeForce GTX 260, on the contrary, does have these diodes. Graphics cards stock coolers were tested in three modes: with the fan in automatic rotation speed mode, at moderate level of noise that was determined subjectively for each graphics card, and at maximum fan rotation speed.

Besides the stock coolers, we also tested Radeon HD 4890 with Arctic Cooling Accelero TwinTurbo in three rotation speed modes of its two fans:

We used this cooler with the same VRM2 heatsink without a fan, just like the T-Rad2 GTX. I wouldn’t recommend leaving voltage regulator components of the Radeon HD 4890 card without any cooling at all.

We have also included a well familiar Arctic Cooling Accelero XTREME GTX 280 into the tests on GeForce GTX.

We tested its cooling efficiency in three fan rotation speed modes too.

Cooling Efficiency Tests

Radeon HD 4890

Before we move on to the main diagram with the test results, let’s compare the efficiency of Thermalright T-Rad2 GTX with one 120 mm fan and with two 92 mm fans. Two 92 mm fans have already been discussed in our today’s article, and as for the 120 mm fan, we picked a pretty quiet Noiseblocker NB-BlackSilent XL2, which rotation speed was set at 1380 RPM with the help of the controller. In terms of generated noise, this mode is only a little louder than with two 92 mm Thermalright fans at 1530 RPM. Let’s take a look at FurMark results:

Thermalright T-Rad2 GTX + VRM2
2x92 mm, 1530 RPM

Thermalright T-Rad2 GTX + VRM2
1x120 mm, 1380 RPM

In my opinion, the results are quite predictable and logical. Two 92 mm fans not only cover a larger area than one 120 mm fan, but also have higher static pressure, which is important for T-Rad2 GTX with its dense heatsink array. The advantage of a dual-fan configuration is obvious.

Another thing that I would like to dwell on is the difference in VRM temperatures with VRM1 and VRM2 heatsinks. In our case, VRM2 proved to be more efficient, because its heatsink was parallel to the fan of the tower CPU cooler that I used. However, as you probably understand, this is not a rule, but mostly a specific situation. It is much more interesting to find out how the temperatures will differ when we use a passive VRM heatsink and a VRM heatsink with an 80 mm fan on it. For that purpose we used an open testbed and tested Radeon HD 4890 with Thermalright T-Rad2 GTX and VRM1 heatsink, which gets much less help from the processor fan than VRM2. Take a look at the photos below and the obtained results: 



The results of our tests showed that VRM1 heatsink with an 80 mm fan cools the graphics card voltage regulator components 6-7 °C better than in passive mode. I can’t say that it is a serious difference, especially since the critical temperature of Radeon HD 4870/4890 VRM components is around 130 °C. However, it is present. Here I have to add that when we top the VRM1 heatsink with a fan, it will be very close to the system case side panel (less than 1 cm away in Antec Twelve Hundred case).

So, here is the diagram with the coolers results on Radeon HD 4890:

The only mode where we can compare the results of our main hero against those of the reference Radeon HD 4890 cooler is the moderate noise mode, and even that at a certain stretch. Both, Arctic Cooling Accelero Twin Turbo and especially Thermalright T-Rad2 GTX work at maximum fan rotation speed much quieter than the stock Radeon HD 4890 cooler at medium fan speed. And as you can see, T-Rad2 GTX wins a convincing victory not only over the stock HD 4890 cooler, but also over Accelero Twin Turbo. Note that T-Rad2 GTX working in quiet fan mode at only 980 RPM cools the graphics card 5-8 °C better than Accelero Twin Turbo at its maximum fan rotation speed. It is an excellent result! T-Rad2 GTX’s advantage over the stock HD 4890 cooler reaches as high as 40 °C. Here you should keep in mind that the VRM2 heatsink for the graphics card voltage regulator components helps a lot (in fanless mode, by the way). Without it VRM temperatures hit beyond 120 °C with both: T-Rad2 GTX, as well as Accelero Twin Turbo.

GeForce GTX 260

Unfortunately, Thermalright doesn’t offer any VRM heatsinks for GeForce graphics cards that is why all alternative coolers shows m ore modest results on these graphics cards:

The stricken out value on the diagram indicates that the test was terminated to prevent the graphics card from getting overheated. During the tests on GeForce GTX 260 we notice a huge difference in graphics processor cooling between T-Rad2 GTX and Accelero XTREME 280 GTX. The reason is quite simple and in fact typical of Thermalright solutions: the uneven base that contacts the GPU heat-spreader only in the center, while the base of Accelero XTREME 280 GTX covers almost its entire surface. As for the VRM components, things are not that good by both coolers, just as by the stock GeForce GTX 260 cooler in automatic fan mode. At the same time it is important to understand that the graphics card works at far not the nominal frequencies and besides, you don’t really come across the same operational load in games like the one created by FurMark in this test.

GeForce GTX 275

The situation looks just like in the previous case when we ran the tests on GeForce GTX 260:

Unfortunately, the temperature of VRM components on GeForce GTX 275 is left out this time.

As for the noise created by our today’s hero, I can only say that it is very low even at maximum fan rotation speed of 1530 RPM of two 92 mm fans. Of course, it cannot get even close to the roaring of the stock Radeon HF 4890 cooler or even pretty low noise generated by GeForce GTX 260/275. And even both Arctic Cooling Accelero solutions that competed against Thermalright Т-Rad2 GTX in our today’s test session work considerably louder at the same fan rotation speed than the fans of T-Rad2 GTX.


Thermalright Т-Rad2 GTX with a VRM heatsink is currently the most efficient cooling solution for Radeon HD 4870/4890.once you equip these graphics cards with the cooler from Thermalright we tested today, they stop scaring users with their super-high temperatures. I have to remind you that we tested T-Rad2 GTX on a substantially overclocked Radeon HD 4890, which makes it even more valuable. VRM heatsinks are an inalienable part of efficient cooling system for these graphics cards. You can’t install an alternative cooler onto a Radeon HD 4870/4890 without VRM1 or VRM2. And in this case the opportunity to purchase Thermalright VRM1/2 separately is a definite Advantage of the solution and not a drawback of Thermalright Т-Rad2 GTX, as you may have thought at first.

Unfortunately, we can’t say the same about Thermalright Т-Rad2 GTX in respect to GeForce GTX graphics cards. The uneven cooler base surface has negative effect on the heat transfer from the relatively large GPU heat-spreader to the cooler base plate. Besides, there is nothing that you could possible put over the voltage regulator components. There is also nothing for the NVIO chip cooling included with the cooler. The heatsink that is allegedly designed for NVIO doesn’t fit beneath the cooler heatpipes and doesn’t stick to the chip properly. I hope that very soon Thermalright will also make a gesture towards Nvidia based graphics card owners and will provide T-Rad2 GTX with everything necessary for fully-fledged cooling.

P.S.: As we have just learned, Thermalright is working on the new bundle for T-Rad2 GTX cooler that will include two TR-SL-92-1500 fans. This change won’t affect the price of the solution in any way.