Thermalright Spitfire and VRM Heatsinks Efficiency Q&A
Q1: Can Thermalright Spitfire cool a top-class graphics accelerator in passive mode (without a fan)?
A: Yes, it can, but only inside an open system case or on an open testbed, at nominal frequencies of 725/4000 MHz and under gaming load (in our case it was 3DMark 2006):
If we use FurMark to load the graphics card working at its nominal frequencies, then the temperatures will exceed 100 °C very rapidly and we will need to terminate the test manually. The same occurs when we try using a passive Thermalright Spitfire inside a closed system case (even f the ventilation inside is properly organized), but this time any type or intensity of load will do the trick. At the same time we can assume with all certainty that it is quite possible to have Spitfire cooler in passive mode cope just fine with mainstream graphics accelerators.
Q2: Can I replace the thermal pads from VRM heatsinks for the mainboard voltage regulator components with thermal compound? Will it affect the VRM temperature?
A: you not only can but simply must replace the thermal pads. You shouldn’t be concerned about improper contact between the heatsinks and the VRM components: it is pressed very neatly and securely to them:
You can check out the test results obtained with the default thermal pad and Arctic Cooling MX-2 thermal paste. They speak for themselves (pay special attention to the three temperatures at the bottom of the GPU-Z screenshot):
By simple replacing the default thermal pad on the VRM components with thermal paste allowed reducing the peak temperature of these components by 30 °C! Therefore, we strongly urge you not to use Thermalright’s default thermal pads and apply some quality thermal paste instead that will guarantee efficient heat transfer from the VRM components to the heatsink on top of them.
Q3: Thermalright Spitfire heatsink is designed to accommodate a 140 mm fan, but how much cooling efficiency will be lost if we use a 120 mm fan instead?
A: To answer this question e tested Thermalright Spitfire with two Thermalright fans of different sizes from X-Silent series:
Using the noise meter and rotation speed controller we set up the fans equally in terms of their acoustic performance that is why the 140 mm fan worked at its default 900 RPM, while the 120 mm fan rotated at 1070 RPM. Here are the obtained results:
As you can see, Thermalright Spitfire cooler with a 120 mm fan turns out only 1 °C less efficient in GPU temperature and 3-4 °C less efficient in VRM temperature than with the 140 mm fan. However, if we lower the rotation speed of the 120 mm fan to the acoustically comfortable 800 RPM, then the GPU temperature will increase by 7 °C, which is, in fact, not that bad at all for this temperature range:
At this point the next two questions become quite logical…
Q4: Does it matter in terms of efficiency what fan we use with Thermalright Spitfire: X-Silent or an alternative one?
A: Let’s try to check things out using Noctua NF-P14 fan as an alternative:
It turned out that there is no difference in cooling efficiency if both fans works at the same speed:
Q5: How greatly does the cooling efficiency of Thermalright Spitfire depend on the fan rotation speed?
A: To answer this question we tested Thermalright Spitfire in three speed modes of the 140 mm Noctua NF-P14 fan: 600 RPM, 900 RPM and 1200 RPM. The graphs below show the obtained results:
The graphics processor temperature lowers most rapidly when the 140 mm fan speeds up from 600 to 900 RPM (by 6 °C), and when it speeds up from 900 to 1200 RPM the temperature drops only by 2 °C. Here I have to stress that even in the quietest fan mode the temperatures of the GPU and voltage regulator components remain extremely low for an overclocked Radeon HD 5850.