On May 19th, 2019, MicroBT’s new product launch with the theme of “Ultimate Win-Win, Success Reproduction” was held in Chengdu, China. MicroBT officially released the latest generation of Whatsminer M20 series, a total of five models, equipped with Samsung 8nm chips. Meanwhile, the new LOGO of MircroBT was also revealed which was more vivid with better features.

The nominal parameters of Whatsminer M20 series are as follows.

The highest hashrate model is Whatsminer M20S-68T. The nominal power consumption ratio is 48W/T. EastShore received the M20S-68 bitcoin miner recently, so the third-party independent experience evaluation will be presented as follows.

 

Product Parameters(standard mode)

Brand	WhatsMiner
Model	WhatsMiner M20S
Algorithm	SHA-256
Submodel	68TH/s @ 3300w
Hashrate	68TH/s ± 5%
Power Consumption	3300w ± 10%
Power Supply	With PSU, plug & play

 

Appearance of Whatsminer M20S

The packing of Whatsminer M20S is relatively simple and compact. On the industrial carton is the logo of Whatsminer M20S logo as well as the SN code. Package size 485x230x355mm, weight 12.3KG.

The inside is reinforced with custom-made EPE foams as well as a transparent plastic dust bag inside to protect the machine during transportation.

Whatsminer M20S is equipped with one dedicated 16A 3×1.5mm power cord. (Note: the power plug is only for 16A jack, the miner power plug is also only for 16A power cord interface).

Whatsminer M20S adopts classic single-tube design as usual, size 390x158x240mm, weight 11.4KG.

On one side of Whatsminer M20S is the latest logo and series mark of MicroBT, and one the other side are printed the precautions: check before power on, no touching during operation, moisture proof, use stable power supply, professional maintenance, etc.

Air inlets are set on the side of control board and power interface with metal shield. The fans at the air outlets are not equipped with protective shield.

 

Internal Structure of Whatsminer M20S

Due to the single-tube design, it’s convenient to disassemble Whatsminer M20S. Remove the fixing screws around the control board first, then remove the power line and data cable connecting to hashrate board to remove the control board.

Whatsminer M20S and M10 adopt the same control boards with the same interfaces.

Remove the screws fixing the power supply as well as the screws of connecting pieces on hashrate board to remove the power supply.

Whatsminer M20S is equipped with a new power supply model P20-12-3350-V1 to provide 12V 265A and 12V 12A DC output with a nominal maximum power of 3350W.

Whatsminer P20 adopts high quality materials. In terms of transformer, it adopts the traditional dual-voltage mode of Whatsminer, which is divided into upper and lower parts. With two-stage low-pass, two PFC are responsible for voltage rise and two LLC are responsible for voltage drop. LLC has higher efficiency for voltage drop with less losses.

Whatsminer P20 is equipped with programming interface to control voltage by means of software. Although two inductors and two transformers are adopted with higher costs, it can ensure more stable power supply. One 8cm 12V 1.5A cooling fan is installed at the rear of the power supply for heat dissipation through ventilation. It adopts the way of air exhaustion instead of air blowing to effectively prevent oxidation and moisture intrusion, so it can also be used in some humid mining environments. Moreover, the thickness of power supply case is also good for heat dissipation.

16A Power Connector

Whatsminer M20S uses two 14cm 12V 9A fans modeled PFC1412HE-00 for heat dissipation in the way of air blowing on one side and air exhaustion on the other side.

Remove the cooling fans, the hashrate board and controller adapter board to take out the hashrate board.

The miner chassis is made of aluminum alloy and the hashrate board is inserted and fixed through the grooves designed inside.

There are three hashrate boards in Whatsminer M20S with aluminum heat sinks on both sides. The aluminum heat sink has a high density and the two heat sinks are fixed by 26 spring screws.

When removing the heat sink, we can see the hashrate chips of Whatsminer M20S. The thermal silica gel is added between the heat sinks and the chips. Each hashrate board is equipped with 105 Samsung 8nm ASIC chips coded KF1920.

The aluminum substrate in the rear is coated with thermal grease to directly contact with the heat sinks.

Detailed Dismantling of Whatsminer M20S

 

Installation and Setting-up of Whatsminer M20S

Before the miner is powered on, it is necessary to confirm no physical abnormalities, such as wire disconnection or abnormal noise. Then confirm power socket supports 16A. Once confirmed, connect the miner to power cord and network cable.

The detailed installation and configuration tutorial of Whatsminer M20S will be introduced in another article. So we will not go into details here.

 

Standard Mode Test of Whatsminer M20S

At present, the Low Power Mode has not been enabled, so we has only conducted the 24-hour test in standard mode.

The environment temperature is about 28℃, the noise value is 50db and the switch-on power consumption is 125W. Since two 9A cooling fans are running at full speed of 7200 rpm, the noise has reached 102db.

Within the first 20 minutes, Whatsminer M20S is in auto frequency stage. The hashrate fluctuates between 14-19T with the power consumption fluctuated between 1100-2500W, the fan speed fluctuates between 1000-2200 rpm and the noise is as low as 60db. Such a stage will last a relatively long time after the miner is started every time. The users may feel confused about it, but it’s normal as a matter of fact.

After about 20 minutes, the hashrate will automatically rise to 68T quickly and the running time will be calculated from 0. It’s at this moment that the miner starts its normal operation. The measured power consumption is 3340W and the tested close-in noise is 93.7db.

The temperature on the side of the miner is 45.3℃ and on the air outlet is 59℃. The temperature tested at the cooling fan bearing is 66.5℃.

The temperature at the junction of power supply and hashrate board is 37.3℃ and the temperature at the air outlet of power supply is 48.3℃.

After 24 hours of test, the power consumption will increase slightly with the rising ambient temperature. Since the overall power consumption has exceeded 3000W, the wire temperature is also recorded between 36-39℃. The highest temperature 55.3℃ is tested around the power plug.

After 24 hours of testing on Whatsminer M20S, we got the hashrate as follows: the average hashrate on configuration page is about 69T, and the hashrate received by the btc.com pool within 24 hours is 68.3T. The hashrate is stable and the rejection rate is 0, therefore the power consumption ratio is calculated to be 48.9W/T.

 

Summary

After 24 hours of uninterrupted testing by EastShore, the average hashrate of M20S-68T bitcoin miner has reached 68.3T in the pool for 24 hours with the power consumption of 3340W and power consumption ratio of 48.9W/T, which is in line with the nominal values. Since the power consumption of single miner has exceeded 3000W, the wire and socket load capability should be considered for deployment in mining farms. Moreover, the ambient temperature of the mining farm will also have a certain impact on energy consumption, so the mining farms should have good heat dissipation. Although the noise is slightly higher than that of previous miners, the noise level is sometimes not so important for the mining farms.

Whatsminer M20S has controlled the power consumption ratio within 50W/T to maximize the stand-alone hashrate of bitcoin miner. As the single miner with the highest hashrate in the industry, Whatsminer series have always maintained their consistent style in stable hashrate.