One of the problem with Little Dot Mk VI is the fan noise, I assume that is something that a lot of users will try to tackle with. I have replaced the fan tonight and I'll try to share my experience.
This is the original fan installed in the bottom of Mk6:
And I have replaced them with GELID Silent 8, an entry level computer DIY cooling fan that is widely available in Hong Kong computer arcade.
Air Flow (CFM): 20.72
Bearing: Hydro Dynamic Bearing
Connector: 3 Pin Molex
Current (A): 0.08
Dimensions (mm): 80 x 80 x 25
Fan Speed (RPM): 1600
Noise Level (dBA): 18
I spend about uS$10 for two fans and the screws to mount it onto the bottom plate of Mk6. The original fan is 20mm thick only, you'll need a new set of screws if you go for 25mm (thick) fans like me. The result is indeed amazing, I can't hear the fan noise unless I put my head up close to about 1 ft from the machine. I strongly recommend MK6 owners to roll up their sleeves and get this done. I am sure there are similar products around your computer supplies, look for products that measured at 20db or below if possible.
I have a few questions that I want to check out with other users who have done this before:
(1) The fans are connected to two 3-pin connectors on the main Mk6 board, it is marked clearly so if you look carefully, you won't miss it. The problem is the connector does not come with a housing like those in the PC mother board, as a result, you can plug it in with either side of the connectors, the attached photo will illustrated that, there is an arrow mark on the board but I am not sure what that means. Right now, I have go for the direction as shown on the left of the photo, if you are fluent in computer DIY, please tell us if the arrow mark has indicated a particular direction to plug in the connector
(2) The original fan used by Little Dot is a 80x80x20 fan with ball bearing. Ball bearing fan are good for reliability, but bad for the inevitable noise as there are little steel "balls" inside the drive shaft. 20mm is not a popular standard in 80cm computer cooling fan market, I have checked the space and confirmed that 25mm will fit as well. However after I install the fan and try to fit the bottom plate back to the machine, I noticed that one of the fan is touching the component ( the bigger capacitor?) on the main board (marked red on the photo)
Does you run into same problem? I can install all the screw alright, but seems a bit odd when I can feel the fan is definitely touching the capacitor.
(3) Just in case, the fans should be set to draw air from outside towards the main board, right?