Test Setup :

For our second test with all the heatsink together I chose an older CPU:


AMD Athlon "Thunderbird" 1400 MHz

This CPU produces 72Watt at default speeds and voltage, very close to the current top crop of Socket A CPU's. But when pushed to a speed of 1533 MHz with 1.9v vcore it comes close to producing 100Watt! Cooling this down with air-cooling is always a challenge.

Here are the full specifications of our test setup:

JMke's Test Setup
CPU	AMD Athlon "Thunderbird" 1400 @ 1533Mhz - 1.9v
Mainboard	Abit KR7A
Cooling	Thermalright SLK947-U Thermalright SP-97 Swiftech MCX462-V Scythe Kamakaze Stock AMD heatsink Evercool MAG-01 Evercool CUF-715CA Alpha PAL8045
Memory	1 * 256Mb PC3200 Corsair
Video	nVidia Geforce DDR

We chose to divide the results up into 2 groups as shown below; the high end heatsink will be tested with the CPU putting out 92Watt of heat, while the budget-friendly heatsinks were tested at the default CPU speed (72Watt).

high speed CPU :

Used Fan:

Coolink 80mm fan tested at lowest and highest settings (24-70CFM / 19-44dBA)



The new Thermalright heatsink takes first spot in the ranking, providing us with temperatures that are up 10°C lower then the highest scoring Alpha PAL8045. The Kamakaze heatsink gave us problems when running the fan at its lowest setting, the system would overheat and we were unable to get any results from the Kamakaze at this setting. The Swiftech lags behind of the 2 Thermalright heatsink temperature-wise, but as you will see later on, this doesn't affect overall overclocking performance as much as you might think. We tested the SP-97 in both horizontal (ideal) and vertical position, a small sacrifice of ~1°C is made when shifting from a desktop to tower configuration.

low speed CPU :

Used Fan:

Standard fan: the default fan installed on each heatsink (AMD stock: 60mm / Evercool: 70mm) except for the SP-97 which has the Coolink at lowest setting.

High speed fan: 60mm delta on the AMD stock / Coolink 80mm fan at highest setting on the other heatsinks



Evercool's copper heatsink Copper heatsink takes the lead here in the budget class of this review, but its lead over the Alu/Copper "MAG-01" is very small, making both these 2 heatsinks good alternatives for the default AMD cooler. The SP-97 blows the competition away in this class, but what did you expect from a high-end heatsink anyway? :)


Overclock the Tbird 1.4

The maximum stable overclock obtained with the high end heatsinks, the AMD stock was included for reference.



Interesting results were obtained here; the Swiftech is able to keep up with the SLK947-U although it dragged behind 4-5°C in our temperatures under load test. Its massive copper base is able to cool down the AMD's DIE fast enough to keep the system running stable at 1610 MHz! The SP-97 is able to take the lead here and edges out the competition by a small overclock margin, reaching 1624 MHz with full stability.
The stock AMD Cooler was able to provide us with an overclock of ~1500 MHz, but the heat produced at this speed and vcore voltage was too much for this small heatsink and the system reached the previously configured shutdown temp of 75°C after running 5-10min under full stress. Further proves the necessity of a high-end cooling solution when you want to overclock your newly acquired AMD CPU.

Time for a conclusion ->