he diagram above designates each 120mm intake fan by a blue arrow; the bottom intake which is passive is indicated by a yellow arrow. Red arrows designate 120mm exhaust fans including the 90mm top exhaust; orange arrows indicate additional exhaust via PSU cooling fans.
NZXT's four side panel 12cm fan are essential for any system with mid to high level graphics. Its best attribute insofar as fan placement are the twin 12cm rear mounted fans. Where the ZERO falls short is in the 90mm top exhaust fan. Designed to remove any residual heat the rear mounted fans miss, top mounted fans are an integral element of chassis thermodynamics. Unfortunately they are not mentioned in the ATX Form Factor guidelines and are rarely considered essential to most designs. The power supply continues to be misused as an additional exhaust port simply because most designers do not understand or simply do not care how these elevated temps will affect the power supply and eventually system stability. The ZERO's 90mm is better not used, the problem is NZXT did not take into consideration PSU size standards, ergo any PSU longer then 165mm (6.5") requires you to remove the top fan. Since the PSU I had under those dimensions wouldn't power the BFG 8800GTX I was forced to improvise and re-mount the fan to the exterior.
NZXT has chosen to eschew larger 140mm or 200mm fans for 120mm which are the standard today and therefore relatively inexpensive to procure, cost savings they pass on to the consumer. The side-panel arrangement is very low key and hardly noticeable for those whom are offended at the often ostentatious Gamer style enclosures out there. ZERO sets a new standard for what may be considered a "Gamers case" with its understated, yet sleek ergonomics. The four 120mm side mounted fans are obviously meant to cool modern graphic cards and most likely what will draw consumers to this case. From the fan compliment the ZERO seems to employ a positive pressure environment which is favored for it's elimination of dust. However any belief positive pressure will completely eliminate dust is folk-science since filters and only filters will effectively keep dust out regardless of pressure
s is obvious from their grouping ZERO's side-panel fans will have a substantial effect on airflow. Whether this balance will contribute to the ZERO being a positive pressure case remains to be seen, I wasn’t able to judge fairly due to the absence of a real filter at this location. NZXT didn't simply shove as many fans as they could into a case, the arrangement makes sense. The type of fans used is where this design separates it’s self from the rest, these fans are relatively low CFM models which operate very quietly. Perhaps the case's namesake implies "ZERO" dBA. Below we remove and reverse the side-panel.
Below I've taken a close-up of the 12cm fan model number, I searched the Internet extensively for this model number without any luck, I removed the NZXT sticker off the fan trying to find a maker to no avail. The fan may be a Sunbeam the model number is DF1202512SEDN seen below. I would hypothesize these fans move approximately 15 ~ 30CFM and are virtually noiseless at approximately 20dBA (rated in anechoic room at 1m).