MikroTik CRS312-4C+8XG-RM 12-Port 10GbE Switch Review

MikroTik CRS312 4C 8XG RM Heat Sink
MikroTik CRS312 4C 8XG RM Heat Sink

For well over a year, Mikrotik has teased a new 12-port 10Gbase-T switch. You can see our 2018 coverage of the initial announcement and the 2019 follow-up. We finally have one in the lab and oscillate between extreme excitement and disappointment. In our MikroTik CRS312-4C+8XG-RM review, we are going to show you around the switch, and show why it is both exciting and why it has one feature that prevents it from being a runaway recommendation.

MikroTik CRS312-4C+8XG-RM 12-Port 10GbE Switch Overview

Before we get to features, let us start with the price. The MikroTik CRS312-4C+8XG-RM has a list price of $599, but we got ours for around $500 shipped. That means this 12-port managed switch is under $42/ port for 10Gbase-T. Perhaps the closest competition is something like the QNAP QSW-1208-8C-US at $550 but it only has 8x 10Gbase-T ports of its 12 ports and is unmanaged. The Ubiquiti EdgeSwitch ES-16-XG only has four combo 10Gbase-T ports. That leaves the MikroTik offering in a class by itself in terms of features and pricing. In the rest of the review, we are going to talk about some of the other differentiation points. Price, however, very much limits the competitive offerings.

Here is a quick video overview of the switch:

On the front of the switch, there are twelve 10Gbase-T ports. If you are simply looking for a 10Gbase-T Layer 2 switch, then you can skip to the power consumption part of this review. The first eight ports also function at multi-gigabit speeds (e.g. 2.5GbE/ 5GbE.)

MikroTik CRS312 4C 8XG RM 10Gbase T Ports
MikroTik CRS312 4C 8XG RM 10Gbase T Ports

Instead, of simply offering 12x 10Gbase-T, MikroTik makes four of these ports SFP+ combo ports. You can choose to use either of the ports depending on your physical infrastructure needs. That can include an uplink to a silent and inexpensive 8 port SFP+ switch like the MikroTik CRS309-1G-8S+IN, 1Gbase-T switches like the MikroTik CSS326-24G-2S+RM, or even higher-end 40GbE switches.

MikroTik CRS312 4C 8XG RM Combo Ports
MikroTik CRS312 4C 8XG RM Combo Ports

Along with the combo ports there is a serial console port for configuration, a management Ethernet for OOB management, and a USB port on the front panel.

The rear has two big features: an array of fans and two power inputs. Unlike many other switches in the $500 price bracket, the CRS312-4C+8XG-RM has redundant internal power supplies for A+B power sources. That is a great feature in a low-cost switch like this.

MikroTik CRS312 4C 8XG RM Rear PSUs
MikroTik CRS312 4C 8XG RM Rear PSUs

10Gbase-T runs 10GbE over traditional copper. That great backward compatibility comes at a cost: power consumption and heat. Processing of 10Gbase-T signaling requires enormous amounts of signal processing, especially for longer runs. As a result, the MikroTik CRS312-4C+8XG-RM has an absolutely massive heatsink and heat pipe cooling solution.

MikroTik CRS312 4C 8XG RM Heat Sink
MikroTik CRS312 4C 8XG RM Heat Sink

This is cooled by two fans but there are four fans total. In our testing, we hit 41.8dba for the idle noise and the fans are surely annoying. This is far from a low hum and is instead an annoying fan noise which makes it something you want in an equipment closet instead of being next to your desk. This is an absolute shame. If MikroTik figured out how to make a near-silent switch, this would be even more of a category killer. We saw the Netgear ProSAFE XS708T which was a quiet 10Gbase-T switch and it would have been great to see MikroTik beat that head-on in the market.

MikroTik CRS312 4C 8XG RM Internal From Rear
MikroTik CRS312 4C 8XG RM Internal From Rear

For management, the MikroTik CRS312-4C+8XG-RM can utilize the company’s Webfig or WinBox management solution. We generally prefer the RouterOS for the extra features and ease of use, but MikroTik also has a newer SwOS designed for switches. A trade-off you make is that the network processing engine is not to the same level as you get on high-end switches, so we suggest doing heavy routing, firewalls, and other services elsewhere. As such, it is really up to you how you want to do simple tasks such as setting up VLANs. Many users will use the management tools once if ever with these switches.

Here is the rated performance from MikroTik:

MikroTik CRS312 Performance
MikroTik CRS312 Performance

Power Consumption

We tested power consumption on 120V power since that is common at the edge where these will be deployed in North America, and wanted to share a few notes. The power supplies did not balance load between them when they were both plugged in. Instead, one PSU handled the full load while the other sat in reserve. We tried pulling the power from both ports one at a time and the switch stayed up so the redundancy worked.

In terms of actual power consumption we saw:

  • Idle Power: 25.7W
  • Max Observed Power: 56.8W
  • Max Power from Spec Sheet: 60W

That will vary based on how long your 10Gbase-T runs are, how many you use, and services you are using. At the same time, this level of power consumption is reasonable. It is also possible to get a near-silent 60W 1U box. MikroTik could have made this silent but missed the opportunity.

Final Words

Overall, this is a good switch for the money. In fact, it is probably the best new 10Gbase-T switch you can buy at this price by a wide margin. Other switches in this class do not come with redundant internal power supplies. There are SFP+ based switches in this price range, but none that have the capacity for 12x 10Gbase-T ports.

Where MikroTik again missed is in the noise. Making this switch silent would have been a game-changer. For those with gear that utilizes 10Gbase-T such as small labs based on platforms like the Supermicro X11SDV-4C-TLN2F, this would have been the go-to switch. Instead, due to the noise, we can only recommend it if it is instead placed in an equipment cabinet.

On balance, if you need a 10Gbase-T switch for simple L2 duties, the combination of inexpensive price, features like web/ app-based management, and redundant power supplies make the CRS312-4C+8XG-RM a clear winner.


  1. Thanks for the article and info. You seem to make a great deal out of the noise – who would ever have such a switch on their desk?

    I wonder if the fan noise is like when a switch with a small board is placed in a heavy steel case – more about making you feel better about your purchase than necessary.

  2. Hi Michael. A very common use case for this is when you have a team of creators, e.g. folks editing video. For many of them, the workplace can be desks set in a common room and IT/ networking is someone plugging-in a 10GbE switch so they can access shared storage easily. Also remember, the MikroTik CRS309-1G-8S+IN is a 10GbE fanless switch in a desktop chassis.

  3. If previous Mikrotik switch products are anything to go by, the noise issues will be resolved over the next six months or so. MT tend to run new products’ fans fairly hard at first, until they get a better idea of how much speed is needed for a given temp/load level – the CRS328-24P-4S+RM and CRS317-1G-16S+RM were the same at launch, but both run fully passive at low temp/load now.

    No guarantee, but things tend to advance fairly quickly for MT products in the first 6-9mo 🙂

  4. I totally agree. We actually finished this review weeks ago when we had to order from Latvia because there was no stock in the US. The publishing queue is fairly deep so this ended up getting published now.

  5. Did you look at the temperatures? is it running the fans needlessly or is it actually required to tame it? If not this might be a perfect target forsom noctua fans.

  6. @Michael I have the CRS-317, a sixteen port spf+ box in my study at home. While it’s not on my desk, it’s about 5ft away on an open shelf. That device is mostly silent, but when the fans spin up they’re the loudest thing in the room (bar me on conference calls lol) by some margin.

    So yes, it does happen 🙂

  7. You can always replace the fans with Noctua 40x20mm to have quasi total silence. That’s what I do on my Mellanox switches (because I do not have a garage, basement or attic to put them there.)

  8. We’ve done Noctuas. If we’ve got the AC blasting, its OK. If the switch is full and the temps are over 26C we’ve had issues.

  9. Finally getting out of insane range (now just into ‘not cheap’)! Given I have a media panel I would be putting this in, not a rack, I wish this also came in a width closer to the mainboard but I understand they aren’t targeting average home users with this. I can still probably get this in but it won’t be easy.

  10. Great review and I know this is a year later. Maybe should provide the update regarding the fan noise: I just got one of these and indeed at initial boot up, especially on the routerOS, the thing sounds like an airplane but… I immediately updated the firmware and what a difference it made. Comparing to the ubiquiti unifi US-XG-16 it replaced the fan level is actually now about the same. Very tolerable in an office environment.

  11. No unfortunately, but I did a direct drop in replacement and am not noticing any difference Vs the US-XG-16 which generated noticeable noise but not extremely loud.
    I can also say that before the firmware update, I completely concur with the review. The thing was way too noisy to be kept in an office space. The lower fan speed from the firmware update made a significant difference.

  12. Coming in a bit later again; I bought one of these and received it today.

    I agree 100%, it was too loud. I’ve installed it in a garage with some other equipment (2 Synology NAS and a few other bits and pieces) and it EASILY drowned them out; not just that, but it was at a significantly different pitch and was very noticable.

    After about an hour when things were cabled up etc I upgraded the firmware to current stable version; I’d guess that noise has dropped by 70%. It’s not really audible above the NASes now.

  13. Hi all, for 8 port 10gb is support speed 1 gb to?
    in this article mention multi speed 2.5g or 10gb.

  14. The firmware from Mikrotik is quite buggy. The dual boot failed entirely out-of-the-box on a new unit. The solution tech support gave me resulted in a boot loop that took me a while to solve.

    And the current version of SwOS (v2.12) doesn’t do multi-gigabit correctly (i.e. 2.5gbe doesn’t work right now).

    The hardware seems good, but the firmware has been abysmal. And reviewing their forums, others are having similar problems.

  15. I have the MikroTik CRS312 connected to 4 PCs and my current 1Gb switch (Trendnet TEG-24WS), where my domain controller and router are connected. The 4 PC are attached with the QNAP QNA-UC5G1T USB 3.2 Gen 1 to 5GbE adapter. The PCs with not connect to the DC and thus the network. I have repeatedly reconfigured and reset the CRS312 SwOS and updated the FW 2.12. I have also tried connected the CRS312 to my CRS309 which is working and communicating to the DC, and network. Perhaps some “Uplink” issues, I assumed automatic. Any suggestions is greatly appreciated.

  16. Note that the 10Gbase-T is limited to 30m on the CRS312, rather than the full 100m as per IEEE 802.3an-2006. Thus, the benefit over DAC/AOC is rather marginal and is more about supporting other devices that come with RJ45 and not SFP+.

  17. Multi-gig is straight up broken on SwOS 2.12, and only hits 500Mb/s on 2.11. RouterOS 6.48.1 also did not work. I upgraded to 6.49beta11 and it finally works. Took forever to troubleshoot, I hope this helps someone out.

  18. I can only agree with this. Only 1G/10G ports are detected on the CRS312. 2.5G is not detected at all and the 2.5G ports just stay offline. When connecting a 100M-IOT device in the switch, we have port “flapping” on the other 10G ports. This only happens after a few hours. I have never spent so much time debugging on a switch. I am now on long time support, but I only want to switch, I don’t need router functions and Mikrotik doesn’t even get that right. I was used to different from other switches and am disappointed with mikrotik. Other switches ran for months/years without any problems. I might try to sell all my CRS3xxx switches to get something better again. The products are not sophisticated in my opinion.


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