FAN DESIGN

Even before we removed one of the fans from the DuOrb we knew that this fan was not going to be your usual 80mm fan; as anyone can see this lil’ guy has 11 fan blades instead of the more standard 7 or 9 blades. When one does make the effort and removes one of the fans from the DuOrb, Thermaltake’s choice in fans becomes clear. As you can see in the above picture the fans used on the DuOrb is an 80X80X20mm Everflow fan. However, unlike past versions of the TT-8020A which were ball bearing design fans in this iteration, this is a sleeved bearing fan. You can tell this by decoding the Everflow model number.

Here is a full break down on what the Everflow T8020SL model designation means: T stands for “tripod” or in this instance frameless, the 12 is for the voltage it runs at, the 80 is for the frame size, the 20 is the thickness of the fan, S is for sleeved bearing and the L refers to the fact that this is the low speed variation of the fan. In any case this fan rotates at a nominal 2000rpm and produces a moderate 37.67 CFM with 1.27mmH20. Since there are two of these fans the total CFM does rival that of many high performance single 120mm fans. Even though the static pressure is fairly low this should not matter as this cooler has obviously been designed with low pressure fans in mind (as shown by the widely spaced, small fins).

The fan had a lot of shaft “slop” or forwards and backwards motion to the fan blade assembly; however, the fan was very tight when pushed off center and displayed very little angular slop. This combination is very common in sleeved bearing fans and is nothing to worry about.


One interesting thing about this fan is the fact that it uses the older style 3 pin fan header. It is understandable why this was done since it enhances compatibility with older systems but it also limits fan speed regulation to variable voltage only. This is certainly not a big deal as this fan is easily controlled via voltage changes (as confirmed by the inclusion of the fan voltage regulator).

On the positive side, the fan cable is long and is completely sleeved. It is always nice when the manufacturers take the time to do this as it makes for a both a cleaner/neater install while also helping to keep air flow restrictions to a minimum.

Rather that rely on MTBF numbers, an easier and better way to get a “feel” for what the manufacturer thinks is the real length of time a product should last is to simply look at the length of warranty provided. The length of warranty has been calculated to be long enough so that customers feel secure in purchasing it BUT still short enough that it will be “out of warranty” when most fail. Taken for what it's worth, the DuOrb comes with a 1 year warranty.

Overall these fans felt and acted like most sleeved bearing fans we have examined and used in the past, i.e. they are classic examples of what a good, quiet, low cost fan should be. Everflow once again does not disappoint us when it comes to making good value added products. The only point of issue is the fact these fans only 80mm low profile 20mm fans; we would really have preferred to have seen the DurOrb with dual full height 92mm fans that produced at the very least more CFM and preferably more mmH20 static pressure. All in all they are good examples of what an 80mm fan can and should be, but in the end those lil guys are still doing a job that really calls for bigger fans.