The motherboard

Skulltrail Motherboard: Intel DX5400XS Dual Socket Motherboard

The Yorkfield CPU is only a small element of Intel’s Skulltrail Platform. The real magic is the Intel D5400XS motherboard. The motherboard is built around the Seaburg-platform and features 44 PCIe lanes, PCIe 2.0 support, and four channels of DDR2 FB-DIMMs at 800MHz. The motherboard is equipped with 4 PCIe slots and allows BOTH AMD Crossfire and NVIDIA SLI.

Intel has not licensed SLI technology from NVIDIA – they purchased NVIDIA nForce 100 MCPs to enable support for SLI. These nForce 100 chips allow a maximum of two GeForce graphics cards to work together. It’s possible to do SLI with two GeForce 8800GTX’s or “Quad SLI” with a pair of dual-GPU graphics boards such as the GeForce 7950 GX2. NVIDIA has stated: “The nForce 100 SLI MCP will NOT support 3-way SLI. This cannot change even with a driver/bios update.”

The rest of the motherboard has all of the essentials: a Sigmatel 7.1 Dolby Home Theater certified high definition audio with integrated optical output, an Intel GigE network controller, 10 USB 2.0 ports, two 1394a ports, 8 SATA ports including 2 eSATA ports on the rear. Power is supplied by a 24-pin main power connector, two 8-pin EPS12V secondary CPU connectors, and a 4-pin auxillary power input.

Enthusiast Friendly

Beyond the specifications sheet, the Skulltrail motherboard has some exceptional enthusiast-friendly features. First of all, Intel has over-engineered the power regulation for the CPU and memory. Second, Intel gave users the BIOS features needed to take advantage of these features. You can adjust the voltage of every component on the motherboard independent, change the bus speed, and even the multiplier. We did not see a clock divider feature, but did not have time to explore this in detail.

During our time with the system, we came to appreciate several other user-centric features. Like the original DFI LanParty NF4 motherboards, Intel’s Skulltrail board has power and reset buttons on the motherboard itself. Intel has added a blue LED for HDD activity on the motherboard itself. This is a system that can be easily run on a test bench without a full chassis.

Intel’s expertise in the enterprise world trickles down to the Skulltrail board as well. Instead of a simple “reset CMOS” jumper there is a Diagnostic Mode jumper. When this jumper is switched, the system will automatically boot into the BIOS system setup. You can choose to reset your password at this time or you can simply make changes to your various BIOS settings. When you save your changes, the system reminds you to turn off the system and replace the jumper to the original configuration. Intel’s flash BIOS utility is also the best in the industry. I found this out first hand.


I’ve bricked motherboards with built in recovery BIOS tools and even bricked motherboards where the flash utility is launched from the BIOS because it misread a sector on the floppy. Sometimes, you’re just unlucky. Sometimes the manufacturer says they support Vista x64, but they really don’t.

I had a predicament with the Skulltrail board Intel sent. First of all, it was running an Alpha BIOS release. Second, I was having stability issues where the system would randomly hard lock. Third, the Beta BIOS update I was given two weeks ago would probably fix my bugs. Fourth, the BIOS download from Intel was a Windows application.

I tried running a set of initial benchmarks just in case I bricked the motherboard, but the system was too unstable to even complete a set of benchmarks. Finally, I threw caution to the wind and decided to run the BIOS update.

Every time I flash an Intel motherboard, I am reminded of how cool Intel’s Express Update is. Although you run the application from Windows, the Intel Express BIOS installs itself, reboots the system and automatically flashes the BIOS for you from the protected environment. You get convenience and security!