GlacialTech GT12025 SDLA1, EDLA1 and BDLA1
Three budget 120 mm fans from GlacialTech Company are among the most popular and widespread retail solutions due to the good reputation of the manufacturer as well as pretty democratic prices. We are very curious to see how well they will be able to compete against more expensive and distinguished solutions. Maybe we should spend that much money on fans after all?
The fans manufactured in China come in simple OEM packaging without any accessories. They look quite simple: black frame and black blades sitting on four supporting rods:
These fans are 120x120x25 mm big and their weight doesn’t exceed 147 g. each fan has 7 blades and the rotor is 40.5 mm in diameter. The fans work with constant speed of 950 RPM (±150 RPM). At this speed they should create 0.75 mmH2O static pressure, 36 CFM airflow and no more than 18 dBA of noise.
The fans with pretty unpretentious exterior have aggressively curved blades with rather large sweep area that expand from the rotor towards the frame:
The difference between the fan models within this series is only in the bearing type. There are four different bearings used for these fans: SLDA1 - sleeve bearing, BDLA1 - double ball bearing, EDLA1 – enhanced sleeve bearing, and HDLA1 – hydrodynamic bearing. Unfortunately, we didn’t manage to get a fan with the latter bearing type:
The sleeve bearing MTBF is 26,000 hours; the double ball bearing MTBF is 50,000 hours, the enhanced sleeve bearing MTBF is declared at 35,000 hours and the fan with a hydrodynamic bearing should last at least 80,000 hours. The interesting thing is that GlacialTech doesn’t differentiate between the fans according to their noise levels depending on the bearing type used, because the declared noise for all fan models is the same - 18 dBA. The fans also do not differ in their official power specs: all of them can work at voltages between 7.5 and 13.8 V, support 0.12 A current and consume no more than 1.44 W of power. At the same time, our measurements showed that the fans differ indeed significantly in power consumption and acoustic readings, which depend on the type of the bearing employed.
Take a look yourselves:
GlacialTech fans featuring almost the same airflow characteristics turned out dramatically different in noise levels. The solution with a sleeve bearing didn’t appear the quietest – it reaches the acoustic comfort zone only at 730 RPM. We can hear the bearing rustling over the entire speed range. The ball bearing model made even louder noises, but it was still ok to tolerate at 810 RPM. The quietest of all was the EDLA1 model that was free from any bearing defects. Its speed in acoustically comfortable mode was 930 RPM. The airflow readings of all fans were a little above the average of the today’s testing participants. Their power consumption is very low, which means that they must have played it safe in the specifications. The startup voltages are quite high for all fan models: SLDA1 – 10.2 V; BLDA1 – 9.0 V; EDLA1 – 9.3 V.