CoolJag JVC682A K8 Heatsink Review

The CoolJag JVC682A is designed for current AMD Athlon 64 processors. Here is an overview of the system and testing methodology.

Soltek SL-K8AV-R
Athlon64 3200+ 1MB L2 Cache
CoolJag JVC682A
AMD Retail Heatsink

Motherboard Monitor was used to obtain and record system temperature information and a game of FarCry provided the processor usage.

Editors note: Even though the Windows XP task manager reported 100% processor usage we could never attain a 100% of the rated heat output as documented by AMD (see below) when using FarCry as a basis for that heat production. Knowing this the game was played until the maximum temperature was attainted and stabilized, or when the round was over.

Other things to consider when judging software induced heat output.
a) Clock throttling by the processor at high temperatures.
b) Normal software isn't designed to produce maximum heat output.
c) Variances of cooling temperature.
d) Variances in CPU load.
e) Inaccuracies in thermal diode readouts.
Of course the list goes on..

My testing methodology is aimed to provide a real world look into this heatsink given the test system provided.

At default speed both the CoolJag JVC and stock AMD heatsink are pretty well matched up with the CoolJag coming in at only a degree less.

A C/W rating can quickly be calculated using this formula.

C/W = (CPU temp - Ambient temp)/(Variance(%) * CPU Watts)
Allowed variance for this test = 75%
CPU Watts = 89W

0.22 C/W = (43C - 28.5C)/(.75(89W))

For this next test the FSB was cranked up to 235Mhz and the test was re-run. To calculate a new C/W rating for this test we will need to factor in the increased processor wattage. The formula and constants for this are listed below.

ocC/W = dCPU Watts * (ocMhz / dMhz) * (ocVcore / dVcore)²
ocMhz = 2350
dMhz = 2000
ocVcore = 1.70
dVcore = 1.50
The variance still applies for our C/W calcuation
Allowed variance for this test = 75%
CPU Watts = 134W

0.23 C/W = (52C - 28.5C)/(.75(134W))

Each of the tested heatsinks come with a thermally controlled fan, during these tests the fan RPM was monitored to see how efficent each fan was relative to the heatsink. In this case lower RPM is better.

As you can see from the C/W calculations the thermally controlled fan helped remove the extra heat produced by the hot Athlon64 without raising the relative C/W rating. The resulting CPU temp is still fairly high but what do you expect for a summertime heatsink test. .

Keep in mind these calculations are provided for demonstration purposes only and may not reflect the actual lab tested C/W rating, but I think I'm close