Intel Skulltrail Preview

Like the Bugatti Veyron, Concorde, and Apollo Space Program, there exist visionary projects that are meant to deliver a new standard, and show the world what the combined engineering capabilities and passion of an entire company or country can do. In 2008, Intel will be releasing their own engineering powerhouse, internally codenamed: Skulltrail. Their mission? Develop the ultimate gaming platform.

In the design of Skulltrail, Intel started by looking at their flagship workstation product: the Xeon-based “V8” platform. While the eight-core Intel V8 offered superb desktop performance, it was limited by memory bandwidth and a workstation-centric design (Serial Attached SCSI, no IEEE-1394, no NVIDIA SLI support).

The heart of Skulltrail: The CPU

The evolution of the “Clovertown” based Intel V8 has brought Harpertown, a quad-core Penryn-based CPU fabbed at 45nm. Not only does this provide better clock-for-clock performance, but the advantages of 45nm manufacturing mean better performance-per-watt (and overclocking potential). Although Intel uses separate sockets for the Core 2 Quad and Xeon line up, the “Skulltrail” edition Core 2 Extreme CPUs will be in a Xeon package, but feature desktop-optimized prefetchers.

Unfortunately, the Xeon package means that FB-DIMMS are required rather than standard memory modules. FB-DIMM is not an inherently flawed design and modern CL3 engineering samples show that the FB-DIMM has the potential to be just as fast as regular DIMMs. By going with a fully-buffered design, the Skulltrail platform will run more efficiently with larger memory capacities including 16GB and beyond. Peak bandwidth is rated at 28.4 GB/sec – thanks to support for 800MHz memory support. The real consequence of FB-DIMMs is not performance, but cost. I guess that’s what a “cost-is-no-object” design philosophy will do.

The Skulltrail 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 Seaburg chipset also supports dual 1600MHz front-side buses.

The real innovation in the Skulltrail platform is the incorporation of NVIDIA SLI support. To enable SLI support, Intel incorporates two NVIDIA nForce 100 MCPs which act as a PCIe to PCIe bridge. Although the motherboard is equipped with 4 PCIe slots, Intel has not licensed SLI technology from NVIDIA -- Intel purchased NVIDIA nForce 100 MCPs to enable support for SLI. This would be the equivalent of a manufacturer building SLI compatibility into an AMD (ATI) developed chipset or an Xbox 360 adding an Emotion Engine for PS2 compatibility.

As important as the chipset and ancillary support for both major multi-GPU designs is the motherboard design itself. Knowing that Skulltrail will ultimately fall into the hands of the most passionate enthusiasts, Intel has overengineered the power regulation for the CPU and memory. This should translate into the best overclocking potential, ensuring that power delivery to the CPU is adequate even when running at higher voltages. That’s right – Intel will be shipping Skulltrail with an overclocking-capable BIOS.

Legacy ports have been removed from the motherboard, but all of the basics and not-so-basic features are there: eSATA ports in the rear, IEEE-1394, and an on-board sound card with digital S/PDIF. All of the chipsets are passively cooled and feature user-replaceable heatsinks, allowing end-users to change the thermal interface or even change the cooler itself.

Although the final cost of the motherboard has not been finalized, we estimate something in the range of $300 to $500 (I know, it’s a big range). Due to the cost of the machine, Intel is expecting the majority of Skulltrail systems to be sold to premium PC manufacturers such as HP (VoodooPC) and Dell (Alienware). Still, Intel will also be offering the motherboard alone to allow DIY’ers to build their own ultimate gaming machine.

How fast is Skulltrail? Try 20,354 3DMarks and a CPU score of 7562. Of course, that’s with a water-cooled engineering sample, 800MHz CAS 5 FB-DIMM modules, and eight cores running at 4.4GHz each. To put things in perspective, that Skulltrail system would have been the fastest supercomputer in the world in 1993.


We’ll have an in-depth review of Skulltrail as the release date approaches.