Synthetic Temperature Test Results:

With the large hunk of copper bolted to the base of the aluminum extrusion we were surprised to see the 5E34B3 offer average performance in out tests. Perhaps the interface between the 4mm thick copper plate was not as thermally conductive as it could have been were it bonded metal-to-metal.

Still, any heatsink which comes in under the 60 degree mark is in range for good performance on a non-overclocked system. However, as we mentioned, the effect of two thermal interfaces can not be the best possible situation for any heatsink attempting to move heat from the base to the fins quickly and efficiently.

With a rise above ambient temperature of 32 degrees Celsius the Spire 5E34B3 is not one of the most impressive heatsinks we've seen, but rather an average performer. The copper base plate spreads the heats along its' entire length, but the layer of thermal compound acts as a stumbling block as the heat travels upwards to the extruded aluminum fins.

Acoustic Sample: Spire 5E34B3

The 5E34B3 uses an in house fan labeled FD06015B1M that is rated at 0.17A so it is not quite as powerful as the well known 25mm high Delta's. We have a sample of the 5E34B3 recorded from its start-up and running condition so you can hear for yourself how much noise this heatsink creates. Shown below are the spectral and waveform images of the noise that was produced by the heatsink and fan. The noise is combination of the fan, and the particular characteristics of the air moving through the 5E34B3's fins. Listen to this heatsink by clicking on the headphones.

The intensity of the sound can be gauged by the waveform image. Generally the smaller the height of the waveform the quieter the heatsink will be. This fan and heatsink combo is on the middle of the range in terms of noise output.

Conclusions:

Despite having a large piece of copper directly in contact with the heat source, the Spire 5E34B3 seemed unable to fully take advantage of the copper's best properties. Since the heat from out synthetic test apparatus had to traverse not only the first thermal interface, but also one from the copper to the aluminum it seems like some of the effectiveness was lost.

Spire have to be given credit for the idea to bolt on a large piece of copper to help spread the heat over a greater surface area of the extruded aluminum, it just that by forcing the heat through a region of silicon based thermal compound it not that efficient.

At best the Spire 5E34B3 manages average cooling performance, but unfortunately cannot position itself as a performance cooler.