LGA775 Heatsink Group Test

Zalman CNPS9700LED:

CPU Socket Support: AMD 940 / 939 / 754 / AM2, Intel LGA775, Intel S478
Weight: 773g
Size: 142mm x 124mm x 90mm

Price (as reviewed): £34.00 (inc VAT)

The Zalman CNPS9700 is the latest incarnation of a fairly old design. However, this latest addition to the line-up is a larger version that uses a 92mm fan. The design is the same as its smaller brothers in the CNPS9500 series, with three heatpipes transferring heat from the base into an array of fins that surround the LED fan in the middle.

The heatsink is an all-copper design and it uses the same mounting system as the CNPS9500 too. Bearing this in mind, we don't need to go over the installation again as it is essentially the same. If you want to read about the installation procedures, please flick back a page.

Performance:

With the fan at full speed, the CNPS9700LED delivered the best CPU temperatures in this group test, showing an increase of only 22°C above ambient at load, and 12.8°C above ambient at idle. Under load, this was a 25°C drop in temperature over the stock Intel cooler! Temperatures on the PWM heatsink were also very respectable too at 45.3°C loaded and 35.9°C at idle.

It’s not all plain sailing though, as the noise produced by the CNPS9700 at the full 2800RPM was a little too much for our liking. In fact, it was far from being practical for 24/7 usage if you don’t wear ear plugs at night time. The only occasion where you’d run the fan at full speed is when low temperatures and stability are the main concern. There was a constant drone, along with a whooshing from the airflow. I don't believe that this could be masked, even when mounted in a case (believe me, it can’t. I’ve tried to myself – Ed).

At this point, we used the supplied Fanmate 2 to reduce the fan noise to more acceptable levels. With the dial set to halfway (around 2200RPM according to PC Probe), there was a decent reduction in noise, and a corresponding increase in both load and idle CPU temperatures. These temperature increases were far from alarming though and only a few degrees at most. Unfortunately, at this speed the droning was still present, as was the air-noise.

We then reduced the fan speed to the lowest setting, which was virtually silent. There was only a slight whoosh, even right next to the heatsink, and the droning had completely disappeared. The performance obviously suffered from the reduced fan speed (now running at around 1250RPM), but even with the fan set to its lowest setting, the CNPS9700 was the third best performer across the board. At 56°C loaded it still improved on the stock cooler by just under 20°C, so is clearly a worthy upgrade, even on it's lowest speed.

Conclusion:

In terms of pure numbers, the Zalman CNPS 9700LED is the clear winner of this group. At full speed, nothing really came close to beating it in any measurement. However, the noise produced at full speed is, in my opinion, too much for all but extreme uses. With a reduced fan speed, the CNPS9700 was much more bearable, though the corresponding increase in temperatures results in it being outperformed by the Noctua NH-U12F and Asus Silent Square Pro.

The Asus Silent Square Pro is available for nearly £10 less, but we'd pay the extra tenner for the far superior mounting system. On the other hand, the Noctua is slightly more expensive, has a better performance to noise ratio, but is unfortunately let down by an overly complex mounting system. Those willing to pay the 9700's asking price, will be rewarded with a cooler that's easy to install, and shows excellent performance across a range of fan speeds and noise levels.