PCB Design

A first impression about a product means a lot. If the mainboard looks good to you at first sight, you are willing to put up with its flaws later. That’s exactly the case with the Infinity 975X/G. Its rather low price, the good reputation of the manufacturer, and a few nice trifles implemented in the mainboard make one’s first impression about it favorable.

Let’s start with those trifles. Saving hard on the accessories and additional controllers, DFI didn’t try to do the same with the CPU power converter.

It is a six-channel converter on the Infinity 975X/G, incorporating high-quality capacitors from Nichicon. The MOSFETs in the CPU power circuit don’t have any cooling means, but they don’t really need any. The six-channel design guarantees low load on each of the channels, and the temperature of the MOSFETs is rarely higher than 40-45°C as a consequence.

A curious solution is employed to cool the mainboard’s chipset. While the leading mainboard makers are installing elaborate coolers with copper and heat pipes on their chipsets, DFI takes it easy:

There is just an aluminum needle-shaped heatsink on the chipset’s North Bridge which proves to be sufficient for cooling that chip. The manufacturer only recommends to mount a fan on it if you use a CPU cooler that doesn’t blow at this heatsink.

The South Bridge is covered with a ceramic plate about 1.5 millimeters thick. Thanks to its porous texture, the plate adds some originality to the mainboard’s appearance and also ensures a proper heat transfer.

Another nice trifle is the two micro-switches that serve as Power On and Reset buttons. They are indeed very helpful when you’re running your system without a system case.

The expansion slots are placed properly. The installed graphics card doesn’t block the latches of the DIMM slots. Besides that, the first PCI Express x16 slot is shifted away from the rest of PCI and PCI Express slots so that graphics cards with massive dual-slot coolers wouldn’t block any other expansion slot.

The only thing we can complain about is the position of the power connectors. They are behind the CPU, near the PCI Express x1 slot. It means that the thick ATX power cables will go right above the CPU cooler, interfering with its airflow.

The mainboard’s back panel offers a standard selection of ports: two PS/2 for the mouse and keyboard; four USB 2.0; one parallel port; one eSATA; one LAN port (RJ-45) with diagnostic LEDs; one FireWire; six analog audio jacks; optical and coaxial SPDIF outputs. The mainboard also has two serial ports, which are implemented as onboard headers.