X-bit labs

Workstation Processors Duel: AMD Opteron against Intel Xeon (page 9)

Category: CPU

by Ilya Gavrichenkov

[ 12/21/2005 | 08:44 PM ]

We’d like to draw your attention to the way the CPU sockets and the DIMM slots are placed on the PCB. They occupy the right part of the mainboard and are located in such a way that these components could be cooled with the fans on the front and rear panels of a rack-mount system case. The air stream is also expected to cool the CPU voltage regulator and the E7525 North Bridge which is capped with a passive aluminum heatsink.

The Intel E7525 supports 24 PCI Express lanes in total and 16 lanes are attached to the graphics PCI Express x16 slot on the Supermicro X6DA3-G2 – this slot must be present on any high-performance workstation. The remaining 8 lanes are divided into two interfaces. The first four lanes are attached to the second PCI Express slot which is logically x4, but physically designed as PCI Express x16. It means that the Supermicro X6DA3-G2 may theoretically support two graphics cards in SLI or CrossFire mode if the graphics card manufacturers take care of that. But even without the appropriate driver support, you can install a second graphics card into the second PCI Express slot and connect more monitors to your system.

The other PCI Express x4 bus connects the North Bridge with the onboard controller Intel 6700PXH which is responsible for the three PCI-X slots available on the mainboard: two PCI-X 100MHz and one PCI-X 133MHz. Two onboard controllers (Ethernet and Serial Attached SCSI – SAS) are also connected across the PCI-X interface provided by the Intel 6700PXH.

The networking capabilities of the Supermicro X6DA3-G2 are provided by the dual-port Gigabit Ethernet FW82546GB controller from Intel. The onboard SAS controller, Adaptec AIC 9410W, supports eight SAS ports and RAID 0 and 1 arrays.

The rest of the mainboard’s functionality comes from the ICH5R South Bridge which is well known to us from the desktop mainboards on i875/i865 chipsets. The South Bridge supports two Serial ATA-150 ports, eight USB 2.0 ports, one ordinary 32-bit PCI slot (located between the PCI Express slots), and six-channel AC’97 audio.

Although the ICH5R may seem an out-dated South Bridge, its capabilities are sufficient for a mainboard of this class. Newer South Bridges boast a more advanced audio solution and more USB 2.0 and SATA ports, but the audio section and the number of USB ports are not so important for a workstation, while hard drives are expected to be attached to the SAS controller in the first place, especially since this standard implies compatibility with ordinary SATA hard drives.

The Supermicro X6DA3-G2 leaves a very pleasant impression with its functionality, stable operation and convenient design. This Extended ATX mainboard can be installed in rack-mount cases as well as in “towers”. The mainboard is powered via three cables at once (4-pin, 8-pin and 24-pin). The power connectors are all shifted to the right edge of the PCB so that the cables from the power supply wouldn’t clutter the system case.

The mainboard allows you to attach five fans, including the CPU ones, and offers advanced fan rotation speed control as well as overall system monitoring options. Besides the traditional system status monitoring through the BIOS Setup and special utilities, the mainboard supports the IPMI 2.0 interface that allows collecting system status information remotely via Ethernet connection after you install an appropriate daughter card.

The rear connectors panel of the Supermicro X6DA3-G2 mainboard carries PS/2 ports for the mouse and keyboard, four USB 2.0 ports, two COM and one parallel port, two network RJ-45 sockets and three audio jacks.

In conclusion to this chapter of our coverage we would like to say that the mainboard from Supermicro received our highly positive response, as it combines wide functionality, smart PCB design and high reliability. We would like to emphasize once again that this mainboard is compatible with all Xeon processors, including the Paxville, has two PCI Express x16 slots on board and supports the promising SAS interface. Supermicro X6DA3-G2 seems to be just the ideal foundation for a dual-processor workstation with Intel Xeon CPUs.