TUF Motherboard Thermal Armor
The signature feature of ASUS’ Sabertooth motherboard is the Thermal Armor system. It has evolved over the years and currently comprises a plastic top plate with ventilation holes over the voltage regulator modules around the CPU socket that can be opened or closed, mounting places for two 40mm “assistant” fans, and a heavy steel back plate that serves both to keep the motherboard from flexing under the load of heavy CPU coolers and video cards, and also acts as a heat sink to some of the aforementioned VRMs.
The two helper fans are installed between the CPU and the first PCI-E x16 slot…
…as well as by the rear I/O panel:
In both cases the fans blow air inwards from the outside of the system, although by default they both run in reverse at high speed for 30 seconds at boot time to help remove dust. The fans are fully under the control of ASUS’ Thermal Radar 2 system and can be controlled like any other fan connected to the system. At full speed, these fans exceed 6,000 RPM and emit a high-pitched whine, although you’ll normally only hear this at start time. Even under heavy load, the normal speed didn’t exceed about 4,500 RPM. The fans are definitely audible in this case although not obtrusive. You can configure the fans to run for a period of time after system shutdown to exhaust hot air from under the Thermal Armor shrouding.
The Thermal Armor system can be easily removed, although there are a fair number of screws involved. With the armor off, the Sabertooth Z97 Mark 1 has a more standard appearance. The black heat sinks around the processor VRM modules are much less showy than the heat sinks ASUS uses on their other boards, but of course they won’t normally be visible.
On the back of the TUF Fortifier steel backplate we can see a thermal pad that contacts the bottom of the motherboard, helping to cool the power circuitry between the CPU and the I/O panel.
ASUS has always been a little vague in describing the benefits of Thermal Armor, so I decided to see for myself what it can do. Since the Sabertooth Z97 is festooned with temperature sensors, it was easy to run a simple test: overclock the system as far as I could (which was 44x on all cores at 1.3v), run the AIDA64 system stability test, and record the temperature reported by the onboard sensors without the two assistant fans, with the fans, and with the Thermal Armor removed. Here are the results:
|(@22ºC)||Idle||Load( w/fans)||Load (no fans)||Load (no armor)||Delta (w/fans vs. no armor)|
The results are interesting. Comparing the maximum temperatures recorded with the Thermal Armor and assistant fans installed with the temperatures records with the Thermal Armor removed, 7 of the 9 points measure showed higher temperatures without the armor. The biggest delta is the rear VCORE temperature, which is a startling 10ºC warmer under load with the armor removed. I expected the rear VCORE to show higher temps since the rear assistant fan blows directly over these components when it’s installed. The one real oddity in this table was that the CPU load temperature dropped 5ºC with the armor removed, which I can’t explain, since the Thermalright Silver Arrow heat sink is completely outside the influence of the armor.
It’s also obvious that you should definitely install the assistant fans. In every case except the CPU, load temperatures were higher without the fans. I did try the load test with the fans with the VRM venting open and closed, but I didn’t see any difference in temperature.
ASUS doesn’t position this motherboard as an overclocking monster, but let’s see what we can do anyway in the next section.