Top positive review
Heat and Power Measurements
July 14, 2016
This review is being written the same day I got the modem, so don't rely on it for long term impressions. The setup process went fine and the modem works correctly. I'm getting the speeds that I pay for, same as what I had previously. I purchased the modem because my provider is in the process of upgrading their network, and when the upgrades are complete I'll need a 16 channel modem to remain on my current plan with the new speeds they'll offer. I wanted to write this review to provide some useful data for anyone else considering this model, because it's something I wish I could have found documented for newer modems before I purchased it.
First is the heat produced by the device. I've attached a photo taken with a thermal camera, showing the modem after being in use for 2 hours. It reads 111 degrees Fahrenheit at the hottest point. (Approx. 44 degrees Celcius) This means that the modem is warm to the touch, but not hot.
I also measured the idle power consumption of the modem using a kill-a-watt device. This is with the modem connected to the network and some devices connected via a router having some connections open, but no active downloads or streaming occurring. Idle power consumption averaged at 7.7 Watts.
I like the modem itself, although I'm not sure at this point if I'm going to keep it. Compared to my previous modem, (SB6141) both the power consumption (5.9W vs 7.7W) and heat output (98F vs 111F) are higher. On the plus side, it offers twice as many channels and twice the maximum speed. Considering the performance bump, the difference between the two devices likely means the MB7420 is actually better from a performance per watt perspective. If you need the kind of speed this modem is capable of, it seems like a very good option.