Functionality
The DFI Infinity 975X/G offers the same functionality as any other i975X-based product. It supports every modern LGA775 CPU with both Core and NetBurst micro-architectures. It offers four DDR2 DIMM slots for up to 8GB of system memory. The slots are color-coded to help you correctly install memory modules to enable the dual-channel mode. According to the specification, the mainboard supports DDR2-400/533/667/800 SDRAM, its frequency is selected in the BIOS Setup. Other memory frequencies, besides the standard ones, are not supported.
In the way of expansion, the DFI Infinity 975X/G offers two PCI slots, one PCI Express x1, one PCI Express x4, and two PCI Express x16, but its PCI Express x16 slots work as PCI Express x8 when you install two graphics cards into your system. If you don’t have a second graphics card, the second PCI Express x16 slot is disabled. This allows using the Infinity 975X/G as a foundation for a high-performance gaming station featuring ATI CrossFire technology. There are certain limitations concerning the other PCI Express slots. If you enable the PCI Express x4 in its native mode, the PCI Express x1 slot becomes disabled. But if you need to use the PCI Express x1 slot, you can do that by switching the PCI Express x4 into PCI Express x1 mode. The operation mode of these slots is selected with a jumper.
The mainboard’s South Bridge (ICH7R) supports RAID 0, 1, 0+1 and 5 and Matrix RAID. So, the hard disk drives you attach to the four available Serial ATA mainboards can be united into RAID arrays. NCQ and a data-transfer rate of 3Gbps are supported. The chipset also supports the Parallel ATA-100 port. DFI didn’t stop at that, though, and added an onboard PCI Express controller JMicron JMB360 that is responsible for the mainboard’s eSATA port. This external port for hard disk drives can be found on the mainboard’s I/O panel.
The South Bridge supports the mainboard’s eight USB 2.0 ports, four of which are located on the I/O panel and four more are onboard pin-connectors. To implement IEEE1394 ports, they installed a VIA VT6307 controller: one of its ports is on the mainboard’s I/O panel and the other is a pin-connector on its PCB.
The mainboard’s audio section is based on an eight-channel HD codec Realtek ALC882. It is soldered right on the PCB rather than on a separate Karajan module which is a customary feature of DFI’s LanParty UT series. The mainboard’s I/O panel offers six analog inputs and outputs as well as optical and coaxial SPDIF outputs.
The mainboard provides a Gigabit Ethernet connection by means of an integrated PCI Express controller Realtek RTL8111B.
An important component of the reviewed mainboard is an ITE IT8718F chip. Besides supporting the legacy ports, it provides hardware monitoring options and allows to control the speed of the fans depending on the temperatures read from sensors. The DFI Infinity 975X/G makes full use of the capabilities of this chip, giving you access not only to the readings of the sensors, but also to controlling the fan speeds in the BIOS Setup.
The IT8718F chip is also accessible from Windows through a utility called Smart Guardian. It is included with the mainboard.


Besides monitoring, this tool allows to control the operation of the fans.





