4 - GPU temps, power cosumption & noise levels

Power consumption

We'll now show you some tests we have done on overall power consumption of the PC. Looking at it from a performance versus wattage point of view, the power consumption is not as bad as I expected it to be. The card according to NVIDIA has a TDP of ~95 Watts.

Our test system contains a Core 2 Duo X6800 Extreme Processor, the nForce 680i mainboard, a passive water-cooling solution on the CPU, DVD-rom and a WD Raptor drive.

	Videocard 100% load System Idle GeForce 9600 GT 512 MB 242 165 GeForce 9600 GT 512 MB OC 248 166

The methodology is simple: We have a device constantly monitoring the power draw from the PC. After we have run all our tests and benchmarks we look at the recorded maximum peak; and that's the bulls-eye you need to observe as the power peak is extremely important. Bare in mind that you are not looking at the power consumption of the graphics card, but the consumption of the entire PC.

The monitoring device is reporting a maximum system wattage peak at roughly 242-250 Watts with a GeForce 9600 GT card installed, and that is not excessive at all. So here's my power supply recommendation:

• A single GeForce 9600 GT requires you to have a 450 Watt power supply unit at minimum if you use it in a high-end system. That power supply needs to have (in total) at least 26 Amps available on the 12 volts rails.
• A second GeForce 9600 GT installed on this system requires you to have a 500 Watt power supply unit at minimum if you use it in a high-end system. That power supply needs to have (in total) at least 36 Amps available on the 12 volts rails.

There are many good PSU's out there, please do have a look at our many PSU reviews as we have loads of recommended PSU's for you to check out in there. What would happen if your PSU can't cope with the load?:

• bad 3D performance
• crashing games
• spontaneous reset or imminent shutdown of the  PC
• freezes during gameplay
• PSU overload can cause it to break down

Noise Levels coming from the graphics card

When graphics cards produce a lot of heat, usually that heat needs to be transported away from the hot core as fast as possible. Often you'll see massive active fan solutions that can indeed get rid of the heat, yet all the fans these days make the PC a noisy son of a gun. I'm doing a little try out today with noise monitoring, so basically the test we do is extremely subjective. We bought a certified dBA meter and will start measuring how many dBA originate from the PC. Why is this subjective you ask? Well, there is always noise in the background, from the streets, from the HD, PSU fan etc etc, so this is by a mile or two not a precise measurement. You could only achieve objective measurement in a sound test chamber.

The human hearing system has different sensitivities at different frequencies. This means that the perception of noise is not at all equal at every frequency. Noise with significant measured levels (in dB) at high or low frequencies will not be as annoying as it would be when its energy is concentrated in the middle frequencies. In other words, the measured noise levels in dB will not reflect the actual human perception of the loudness of the noise. That's why we measure the dBA level. A specific circuit is added to the sound level meter to correct its reading in regard to this concept. This reading is the noise level in dBA. The letter A is added to indicate the correction that was made in the measurement. Frequencies below 1kHz and above 6kHz are attenuated, where as frequencies between 1kHz and 6kHz are amplified by the A weighting.

	TYPICAL SOUND LEVELS Jet takeoff (200 feet) 120 dBA   Construction Site 110 dBA Intolerable Shout (5 feet) 100 dBA   Heavy truck (50 feet) 90 dBA Very noisy Urban street 80 dBA   Automobile interior 70 dBA Noisy Normal conversation (3 feet) 60 dBA   Office, classroom 50 dBA Moderate Living room 40 dBA   Bedroom at night 30 dBA Quiet Broadcast studio 20 dBA   Rustling leaves 10 dBA Barely audible

We tested all cards on dBA levels. Obviously the reference coolers all perform roughly the same. The customized coolers are either louder or softer depending on what they try to achieve. Here are the results:.

Graphics card	IDLE	During Gaming
9600 GT 512MB NVIDIA	38	42
9600 GT 512MB Inno3D OC	38	42

You'll notice that all cards perform roughly the same and the reference cooler are doing a pretty nice job. During gaming when the heat builds up in the GPU, the fans will start to spin faster and create more airflow. So in IDLE this is what our PC created noise wise, expect that level of noise in for example desktop mode.

Let's have a look at the temperatures.

GeForce 9600 GT core temperature

Let's have a look at the temperatures these single slot design coolers produce.

	Inno3D GeForce 9600 GT OC

The Inno3D GeForce 9600 GT OC. This product has exactly same cooler as the reference design, though a mild overclock should make the temps rise a little, apparently the temps are even a little lower. Usually we measure at 21 Degrees C room-temperature, this test was done early in the morning and heating didn't kick in yet. I think 17 Degrees C was the room temperature, probably why the measured temp was a little lower than the reference model. All in all, very good though.

Very nice, let's have at some photos of the Inno3D GeForce 9600 GT first.