ASRock Rack E3C242D4U2-2T review: motherboard for cheap server

We love powerful 48-core processors, but not every customer is willing to pay for such power: even among modern companies with a hybrid infrastructure (local + remote cloud), many are willing to make do with 4-6 core servers on entry-level Xeon E-2100/2200 processors. In practice, when you need a solution for a host that runs a security gateway, 1C server, and Kubernetes node, you can even opt out of using ECC memory in favor of desktop processors like Core i5, Core i3, and even Pentium Gold. In General, where you need a high frequency in single-threaded loads, often there is not enough except for a normal motherboard, and here it is in front of you.

Modern server Board ASRock Rack E3C242D4U2-2T on the Intel C242 chipset for such cheap assemblies. Although, why cheap, because on the same platform, you can build both a NAS with cold Celeron on passive cooling, and a full-fledged virtualization host with a 6-core CPU. For large companies, this is an opportunity to have a single motherboard nomenclature for a whole fleet of servers, which means reducing the cost of spare parts. Well, if the customer suddenly asks the question: “how much does the server motherboard for Core i3 differ from the game one”, then do not forget that in addition to the lack of RGB illumination, server motherboards have:

  • Location of memory slots along the purge of rack cases
  • ECC memory support + presence of ECC modules in the compatibility list
  • Built-in IPMI 2.0 ASpeed 2500 controller with dedicated port
  • WatchDog support in the BIOS
  • And guaranteed compatibility with Windows Server, RHEL, SLES, and Ubuntu Server

Oh Yes, I almost forgot: specifically, ASRock Rack E3C242D4U2-2T still has the best 10-Gigabit network controller Intel X550-T2 with RJ45 ports for copper. In other words, you have a modern platform that is ready to become the building block of your hyperconvergent infrastructure.

Memory subsystem

The coffee Lace-S platform has a 2-channel memory controller, and the maximum memory frequency is limited to 2666 MHz. You can only use unbuffered memory with or without ECC support for a total of 128 GB. Registered memory is not supported.

In the QVL list, the main place is reserved for 6 types of 8-Gigabyte modules, which is not surprising, but there are two 32-Gigabyte ECC from Samsung and even one 4-Gigabyte Kingston KVR21N15S8/4 worth $ 15 for very cheap builds, for example FreeBSD nodes.

The gem of the motherboard is 20 gigabits of pure copper speed provided by the Intel X550-T2 controller. The network controller supports PXE, and the first LAN port supports NCSI. In the Arsenal of ASRockrack there are analogues of this Board with a 1-Gigabit network on the Intel i350 chip. As a rule, boards with this controller have an iSCSI download, which is completely absent in 10-Gigabit versions. We recommend to read our comparenment of Aquantia AQC107 against Intel X550-T2 to get acquainted with the network adapter integrated on this motherboard.

In addition, for each of the 10-Gigabit ports in the out-of-band mode, you can access the IPMI interface of the motherboard if there are no available IPMI ports in the rack.

Interestingly, the Intel X550-T2 network controller has a very large heatsink. This is due to the fact that it is located in the same heat flow with the processor and its VRM module. That is, the network is cooled with warmer air than for example in the ASRockRack EPYC3251-2T Board. Why is this done? Yes, the fact is that budget 1U cases often have two 40-mm fans in the center of the motherboard, and their flow, though strong, is narrow, so ASRock Rack adjusts to such options.

Storage subsystem

The motherboard has 6 SATA 600 ports, including SATA DOM with power supply to the flash drive. This port uses a common interface with M. 2 SATA 3, so when you install this module, the port is disabled. Fortunately, this does not apply to M. 2 NAME drives, which can have a size up to 2280 and a PCI E 3.0(X4) interface.

ASRock has a variation of this motherboard E3C246D4U2-2L2T, which has 8 SATA ports and is more suitable for storage, and our ward, in General, does not differ in terms of data storage. Yes, there is a software RAID 0/1/5 that you can install Windows on, but this is not relevant today.

Expansion slots:

The Intel coffee Lace-S platform supports only PCI 3.0, and this is, frankly, the weak side of the motherboard in question. In total, there are three slots on the Board in different constructs, from top to bottom it is:

  • Slot7: PCIE-1x from the South bridge
  • Slot6: PCIE-16x from the processor (divides the speed by 8x/8x with the Slot4 slot)
  • Slot4: PCIE-8x from the processor (divides the speed by 8x/8x with the Slot6 slot)

The presence of an integrated 10-Gigabit controller, of course, helps to do without expansion cards at all, but if you simply need additional controllers, look for the e3c246d4u2-2L2T card, which additionally has a PCIE-4X slot opposite the M. 2.

Power subsystem

In the list of compatible processors there are models with TDP up to 95 W, but of course the majority of options are in the range of 40-50 W, so an 8-phase VRM scheme will be enough. A common 2-phase VRM is used to power the memory slots, while the Intel X550-T2 uses a 3-phase power scheme.

Solid-state capacitors are used for filtration, which, although it looks like an outdated technology, has high reliability and a service life of about 15 years.


For remote control, the ASPeed AST2500 chip is used with a dedicated 1-Gigabit network port, which is only used for BMC functions and nothing more. I would like to say that AST 2500 is the best solution to date, having a modern HTML5 interface optimized for tablets and smartphones. You can use quick and convenient console management and connect a remote disk to install the operating system both from your computer and via the NAS. There is a very convenient temperature monitoring and the ability to record POST-tests.

Compared to the Dell iDRAC, HPE iLO, and Lenovo XClarity management systems, you don’t pay for remote management, but get almost the same features, not to mention the fact that you can simply forget about IP-KVM like a bad dream. Yes, and another thing: if you don’t use a dedicated Gigabit network port, you can access the BMC via a 10-Gigabit port: the Board has a similar network switch, so we can access the hypervisor’s web interface and the BIOS via the console via a single network wire. Cool!

One of the interesting features of the AMI BIOS is the non-switchable watchdog timer, which has 2 server reboot modes: Reset and NMI. You can also enable hardware application encryption (SMS) and configure Turbo Boost for Xeon processors.

Compatibility with OSes

And while the official list of supported OSes is depressingly intimidating with the lack of VMware ESXi, this is the first operating system I installed to make sure everything works.

Compatibility with OS
VMWare ESXi 6.7 U3 Yes
Ubuntu Linux 19.10 Yes
Microsoft Windows Server 2019 Yes
PFSense 2.4.4 p3 Yes
FreeNAS 11.3 Yes

Thus, if vSphere is part of your infrastructure, along with FreeBSD, Windows Server, and Linux, you can use this Board.


Motherboard will fit perfectly in any local office (if it is set in a housing with front connection) and in the data center, this 1U.

In general, similar motherboards on the market abound, and that when you purchase via tender you didn’t sell it ASRock Rack E3C242D4U2-2T, specify in the technical requirements, three PCI Express slots (16x+8x+1x) and 10-Gigabit network card with two ports. This will eliminate the entire range of Supermicro X11 SSH cards, and companies like Ten and Gigabyte do not have MicroATX solutions on Socket 1151 with an integrated 10-Gigabit network adapter.

Overall, considering that its direct competitors have this motherboard no, it’s a great budget solution for Hyper-converged servers.