I first wanted to test the coolers on a dual-core Intel Pentium D 820 that we managed to get, but the ABIT AA8 mainboard does not support dual-core modifications of the Intel Pentium 4 at all (I guess such processors are not supported by the i925XE chipset). So, I had to limit myself to an Intel Pentium 4 506 on an E0 stepping core (2666MHz, 533MHz FSB) which did well at overclocking, being stable at 3800MHz:
I didn’t even have to increase the core voltage to achieve that frequency (it is 1.385V by default). I should confess the processor didn’t react at all to my changing its voltage which was rather strange for a Prescott core. The mainboard’s limit is 244MHz which is a long way yet from the achieved 190MHz, and the memory frequency and timings were set up in such a way as not to restrain CPU overclocking. However, I had to stop at the frequency shown in the screenshot above.
Let’s first have a look at the results I got on an open testbed:
After doing very well in comparison with the Zalman CNPS8000 on the AMD platform, the Scythe Mine fails in this test. I thought that poor contact between the cooler’s base and the CPU heat-spreader might be the reason for this poor performance, but the results didn’t change after I made sure the thermal paste was applied properly and even tried different positions of the cooler’s heatsink and fan. Alas, the Scythe Mine with its stock 100mm fan can only compete with the much cheaper Pentagram Freezone NXC-100 Cu on the Intel platform.
The Zalman CNPS8000 in its turn looks very well on the Intel processor: the temperature of the single-core Intel Pentium 4 at 3800MHz clock rate and under the S&M load is no higher than 49°C even in the quiet fan mode (according to the sensor in the CPU itself). The temperature goes down by 2°C when the fan speed is increased, but I don’t think it’s worth the lost silence.
Now let’s see how these results will change in a closed system case:
It’s no different with the headliners of this review: the CPU temperature is just a little higher with the Zalman CNPS8000 and the Scythe Mine. There are, however, changes in the ranks of the super-coolers with the Thermaltake Big Typhoon suddenly on top, even though not by much relative to its opponents. Somewhat puzzled at this fact, I decided to build a diagram basing on the reading of the mainboard’s PWM sensor located near the CPU socket.
Quite expectedly the coolers that direct their airflow towards the mainboard beat their opponents that have a tower-like design and a horizontal airflow. This affected the result of the Thermaltake Big Typhoon, of course. But the Pentagram NXC-100 Cu and the Zalman CNPS8000 aren’t brilliant at cooling the overclocked processor, having lower overall performance.