4 - Installation | GPU temps | Power consumption | Noise levels

Installation

Graphics cards are pretty easy to install. This card was not different. Slide the card into a free PCIe 8x / 16x slot and connect a monitor. You can now power up the PC. Once Windows boots up, install the latest Catalyst drivers and make sure your operating system is fully patched up, especially DirectX. After driver installation, reboot the PC and you are ready to go.

Power consumption

It's time to do some actual testing with these cards. We'll start off by showing 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 really good with the new 55nm products. Our single card test system is a Core 2 Duo 3.0 GHz / 1333 FSB Processor, the X38 mainboard, a passive water-cooling solution on the CPU, 2GB memory, DVD-ROM and WD Raptor drive. Have a look:

Only 155 Watt, which is really funny to see as it's even less than our typical idle wattage with a mid-range of high-end graphics card. More interesting are the power states of the GPU and memory. It's clocked down massively in desktop mode, we spotted the core clocked at 110 MHz. When it's not utilized and the memory at 300 MHz, as a result of all these power states in idle desktop mode the entire PC was using 115 Watts.

A single Radeon HD 4550 requires you to have a 300 Watt power supply unit at minimum if you use it in a high-end system, and I think that's barely on the safe side. Also recommended is 20 AMP's on the 12 volts rails for stable power distribution (in a single card configuration). Please make note of the fact that the card uses two 6-pin power connectors.

There are many good PSU's available, over the years we reviewed a lot of them and have loads of recommended PSU's for you to check out in there, have a look. Things that can 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

The thermal envelope

We measure GPU temperature at a room temperature of 21 Degrees C at all times during our tests.

Results: we see nice IDLE temperatures at roughly 45 Degrees C.

Once we start stressing the GPU the temp goes up big-time, we level at roughly 70 Degrees C. Though a lot for a low power product it's still perfectly normal though.

Noise Levels coming from the graphics card

When graphics cards produce a lot of heat, that heat usually 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. 

We start up a benchmark and leave it running for a while. The fan rotational speed remains constant. We take the dBA meter, move away 75 CM and then aim the device at the active fan on the graphics card.

The card is extremely silent, thanks to it's advanced power management not only is the power consumption low, also it's heat levels. In idle you can't really even hear the card. We measures 38 DBa from the system. Once the GPU is getting hot by fully utilizing it, we get stuck at a 39-40 DBa measurement which you can hear, but you'd need to concentrate to hear it. Very nice.