Asus P5E3 Premium: A Mean, Green Motherboard?

FAN CONTROL

The extent to which fans can be controlled, and how they behave when left on automatic control is a major criteria for us when it comes to motherboards. For $370, we expect good things. The P5E3 Premium is blessed with six fan headers, most of which are towards the front of the board.

When it comes to customizable control, SpeedFan is our application of choice. If properly supported, it can be configured to raise/lower multiple fan speeds to designated limits when any specified temperature threshold is breached.

As a monitoring program, it is a little less desirable, commonly reporting extra erroneous temperatures and as well as frequently misreading voltages, as in evident in the screenshot above. It does however get the main readings right, reporting 5 fan speeds and getting the CPU and system temperature correct, or at least the same readings as Asus' PC Probe. The fan header labels are incorrect however. To avoid confusion, relabel them to match the table below:

To control the CPU fan header, go into the Advanced menu and find PWM#2. Change its mode from "SmartFanIII" to "Manual PWM Control." Using the Speed02 drop-box, we were able to adjust a Xigmatek PWM fan speed to between 930 and 2520 RPM (3-pin fans run at full speed). We were also able to control all the Chassis Fans with the Speed01 drop-box, but it was very limited — 1400 RPM at 0% and 1500 RPM at 100% using a Scythe Kama Flow 80mm fan.

BIOS Fan Profiles

To test the the different fan profiles available in the BIOS, we first hooked up the Zerotherm CPU fan to a custom DC fan controller and attached a Xigmatek PWM fan to the CPU fan header instead, placing it away from the test system so it would not affect the temperature. Prime95 was then run to heat up the CPU. We set the Zerotherm fan to 5V to ensure the CPU would heat up more than usual. Finally, we tracked the CPU temperature as well as the fan speed of the Xigmatek fan.

The automatic fan profiles are typical of what we've seen in the past from Asus. The changes in fan speed are rather abrupt, increasing in a varying number of steps (depending on the profile selected). The fan speed begins to pick up at approximately 55°C, 50°C and 45°C for the Silent, Optimal, and Performance profiles respectively. Though the Performance profile does increase the fan speed the most, it is far from aggressive as the Xigmatek fan is capable of spinning at more than 2000 RPM.

The Manual profile settings gave us mixed results. The Fan Start-Up Ratios seemed to be accurate — at 60% the fan speed started at 1200 RPM, and at 40%, 950 RPM. The Target Temperature was spot on when set to 50°C, but when set to 40°C, the fan did not increase in speed until the CPU temperature reached 48°C. It's probably better to use one of the automatic fan profiles instead. The Chassis fans, as a group, can also be set to Manual (with the Target Temperature being System temperature rather than CPU) as well as Full Speed and Fixed Speed.