Performance

Test system:

Note:
Idle refers to the computer sitting at desktop for 30 minutes.
Load refers to the CPU running two threads of Prime95's "In-place large FFTs" stress test for 15 minutes.
Temperatures have been taken via RealTemp. RealTemp takes the TjMax value of the CPU into account, providing very accurate results. Read all about it here.


At stock clocks, when idling and at load, the CNPS9900 LED has performed better than all other tested coolers. It beats the stock cooler by 17 degrees Celsius when the CPU is under load. The CNPS9900 LED has performed better than all DHT solutions even though they are larger than it.


Once overclocked, the CNPS9900 LED has again performed better than all other coolers when idling and under load. It runs a massive 36°C (under load) cooler than the stock cooler, which is amazing. That being said though, the Intel Stock CPU cooler that was used was the stock cooler of the E8500, which is the lighter, low profile, totally aluminum cooler. Performance in all tests is exceptional.

Fan Noise

At its low setting (PWM controlled), the CNPS9900 LED is inaudible through the case. You wont be hearing it at all if you have a side panel attached and any other fans within the case. Under hotter conditions, when the PWM sensor increases the fan speed, the CNPS9900 LED was still relatively quiet. While the cooler was definitely louder than what it was when idling, and did become slightly audible even with a closed case, it still remained quiet, which is good for a 120mm fan.

The problem with PWM fans is that the user can not control the noise as they can with a fan controller (as some prefer to have higher temps but lower noise). I would say this is not a problem with the CNPS9900 LED as it is not an annoyance at all under full load, and will only but blend in with case/graphics card/power supply fans.

The Intel stock cooler is marginally louder at stock, but a lot louder when under load or when overclocked. The CNPS9900 LED is noticeably a lot quieter than the Intel stock cooler when running at higher speeds. Having a PWM fan on the CNPS9900 LED is an extremely smart move by Zalman, because the fan is not noisy and is not frustrating to listen to when running at higher speeds.