Closer Look at Intel D2500HN and Intel DN2800MT Mainboards
We are going to study the new Cedar Trail platform using two mini-ITX mainboards with integrated Cedarview-based Atom CPUs. Both are manufactured by Intel which, of course, is in the forefront of introducing its own low-power CPUs into desktop systems.
The heart of the Intel Desktop Board D2500HN is an Atom D2500, the junior model of the Cedarview series. This mainboard is quite a typical implementation of the Atom concept.
The Intel Desktop Board DN2800MT is somewhat more original. Based on the senior netbook-oriented Atom N2800 CPU, its design allows integrating it into slim devices.
Although dissimilar, the two mainboards share two key features. First of all, they offer SO-DIMM slots for memory modules which help save some precious room. Each of them has two such slots and each supports DDR3-1066 SDRAM, but memory works in single-channel mode even if you use both slots. That’s a limitation of the Atom’s integrated memory controller. Another limitation is about the maximum amount of supported memory, which is only 4 gigabytes.
And second, both mainboards cool their CPU passively. A massive aluminum heatsink turns out to be capable of handling the 6.5-watt Atom N2800 as well as the 10-watt Atom D2500. Each mainboard has a 3-pin fan connector, but you don’t really have to install a fan.
The Desktop Board D2500HN resembles Intel’s own implementations of the previous-generation Pine Trail platform but it is based on a 32nm dual-core Atom D2500 processor with an integrated graphics core GMA 3600 clocked at 400 MHz.
Although the junior Cedarview model, the Atom D2500 is a full-featured dual-core CPU with a clock rate of 1.86 GHz, just as most of the Cedarview series. What it lacks is the Hyper-Threading technology which is a very good means of increasing the usage efficiency of the execution devices in CPUs with the Bonnell microarchitecture which doesn’t support out-of-order execution. In other words, the Atom D2500 may slow down in multithreaded applications.
Although the new Atom CPUs allow using digital interfaces to connect monitors, the back panel of the D2500HN offers a meager selection of connectors, just as earlier mainboards of the same class did.
D-Sub is the only video interface available. Besides it, we have four USB 2.0 ports, a Gigabit Ethernet connector, a PS/2 port for mouse or keyboard, and three audio connectors (based on a four-channel codec ALC662). The mainboard even offers a couple of legacy ports: serial and parallel.
There are very few onboard connectors, too. We can see two headers for four USB 2.0 ports, two SATA-300 connectors and a second COM port. Well, we could hardly expect anything more since this meager selection of interfaces is the best the Intel NM10 chipset can offer. The D2500HN does not use additional controllers to cost less. Its price, according to the manufacturer, is supposed to be $60-61. If the capabilities of the D2500HN seem to be too limited, you can install a PCI controller into the available slot.
The mainboard has a 24-pin ATX power connector but you can use a 20-pin PSU cable for it.
The developers of the Intel Desktop Board D2500HN paid their attention to hardware monitoring capabilities which are important for miniature computers. Besides monitoring voltages and fan speed, the mainboard can keep track of two temperatures: CPU and VRM. The speed of the fan can be regulated depending on either temperature.
While the D2500HN is a typical Atom-based Intel mainboard, the Desktop Board DN2800MT is something completely different. Intel developers haven’t yet tried to equip a nettop-oriented mainboard with a netbook CPU. And now they do, and the result is a highly economical and compact mainboard that can fit into a system case that has a height of only 25 millimeters.
As its name suggests, the DN2800MT is based on an Atom N2800 processor, which is similar to the Atom D2550 but has a lower TDP of 6.5 watts.
Like the D2500, the Atom N2800 works at a clock rate of 1.86 GHz, has two computing cores, but also supports Hyper-Threading. The OS will identify it as a quad-core CPU. Its integrated graphics core GMA 3600 is clocked at 640 MHz.
The Intel Desktop Board DN2800MT is designed in such a way as to make sure it fits into very slim system cases, therefore it has no tall components. It even has a half-height back panel. However, the latter offers more interfaces that the D2500HN. Take note that we've got not one but two video interfaces here: an analog D-Sub and a digital HDMI 1.3a. There are also four USB 2.0 ports (two of which have reinforced power supply lines to quickly recharge mobile gadgets), a Gigabit Ethernet connector and two analog audio connectors (based on an ALC 888S codec). The most interesting connector is on the left: it is a power connector.
Yes, the Intel Desktop Board DN2800MT needs to be used together with an external notebook power supply. That’s quite natural considering that it is designed for slim computers. There is no power adapter included with the mainboard, but you can easily find one because it supports any adapter with an output voltage of 8 to 19 volts. There’s an internal 2-pin socket next to the external power connector, by the way. You can use it to power the mainboard up, too.
Although the DN2800MT is positioned as a solution for ultra-compact system cases, it’s got a lot of onboard headers and connectors: two headers for four additional USB 2.0 ports, two SATA-300 connectors and one SATA power connector, two serial and one parallel port, and a PCIe x1 slot for expansion cards. It must be noted that these connectors are all oriented in the conventional way, i.e. they are perpendicular to the mainboard’s PCB, so you may find it impossible to use them in a slim system case.
Intel has provided a means to do without those connectors, though. If you want to use an SSD, for example, you can connect it to the mainboard's mSATA slot which does double duty as a full-size mini-PCIe slot. Besides, the DN2800MT has a second additional mini-PCIe slot for half-length devices.
Another interesting feature of the Intel Desktop Board DN2800MT is that it can be directly connected to display devices via LVDS or Embedded DisplayPort. This may be useful if the mainboard is installed into an all-in-one computer.
The hardware monitoring capabilities offered by the DN2800MT are not as rich as those of the other Intel mainboard we’ve discussed above. It lacks a dedicated temperature sensor, but the fan can be regulated depending on CPU temperature.
Generally speaking, the Intel Desktop Board DN2800MT is a functionally rich and originally designed Atom-based mainboard that can be employed in standard mini-ITX as well as in less conventional computers. Thanks to its design peculiarities and low-power CPU, it can fit into an ultra-slim system not larger than 1 liter in volume. Of course, a specialized product costs more than mainstream ones, so the recommended price of the DN2800MT is $96-101 or about 50% higher than that of the D2500HN.