Zalman CNPS 20LQ Review
To provide continuity the test set up is as always
Gigabyte UD3R V2
Intel i7 950 @ 4GHz 1.25v & 1.35v
Mushkin Radioactive 2000MHz
Cooler Master Storm Trooper
For the first test we set our i7-950 overclocked to 200x20 @ 1.25v for a clock speed of 4.0GHz. We allow the system to idle for 10 minutes and then run Prime95 'maximum heat maximum stress' setting for a further 30 minutes.
After 30 minutes we note the temperatures of all cores and the ambient temperature of the room. An average of all cores is taken, then the ambient temperature is removed from this figure and this gives us the delta temperature. Delta is the temperature difference above ambient which is a truer reflection of the heat-sink performance rather than mere maximum figures. Testing in an Igloo or the Sahara would give vastly different maximum temperatures, yet the Delta could be the same. As this unit is supplied with 2 fans I have tested in both single and dual fan configuration. All testing is done with the fans powered of a 12volt supply from the PSU to ensure that the fans are run at full speed. As the 2000rpm fan fitted to the 20LQ proved to be more than a bit noisy at full tatt I also undertook some testing at a more respectable 9volts to see what effect it would have on cooling at a fan speed that was more tolerable.
The second test follows all steps from above but with a 200x21 @ 1.35v for 4.2GHz overclock, the extra voltage in this test allows us to see if the heat-sink can cope when extreme loads and overclocks are applied. As with 4.0GHz the Heatsink was tested in both single and dual fan configuration. Again we tested at high and low fan speeds.
The last test is at 4.4GHz, 200x22 @ 1.45v and is an extreme test that only extreme coolers will ever pass. Any cooler in this graph is a one of the elite few that has the cooling ability to dissipate the heat created during this grueling test. On low fans the cooler failed with the one of the cores exceeding the limit of 90 degrees required for a pass in this test. At high fans however it remained under the 90 degree limit.