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Intel demonstrated a SkullTrail system at IDF. SkullTrail is a high-end desktop with SLI graphics and two quad-core CPUs. That’s eight cores total.

SkullTrail is designed for Intel’s next-generation Penryn processors.

The SkullTrail motherboard had two LGA-771 sockets. These are Xeon workstation and server sockets. However, the processors used were the desktop processors codenamed Yorkfield.

Some analysts have commented that they do not think there is any difference between the quad-core Yorkfield and its quad-core server counterpart called Harpertown. Both Yorkfield and Harpertown are based on the same process technology and the same second-generation microarchitecture, so they are very similar. However, according to Intel, “there are slight differences in the hardware prefetchers in Xeon vs. desktop Core 2″ (p. 2).

SkullTrail also featured SLI from NVIDIA. SLI was made possible by putting two media and communications processors (MCPs) on the motherboard. “This isn’t an SLI licensing deal; this is Intel purchasing NVIDIA MCPs” (p. 2).

Intel still does not own a license for SLI. So if Intel can do it this way, why can’t others?

SkullTrail, like the V8 before it, performs remarkably well for those applications that take advantage of eight cores. It’s a question of performance vs. “price, power and noise” (p. 2).

Penryn and SkullTrail Benchmarked at IDF

The quad-core Core 2 Extreme has finally achieved “frequency parity with its dual-core counterpart” (p. 1).

One reason why this is important is that some applications perform better under dual-core than under quad-core, because quad-core tends to be clocked lower to compensate for the additional heat that twice as many cores generate.

In most applicatons, quad-core performs better, despite the lower clock speeds. But in other applications, dual-core beats quad because of higher clock speeds and the nature of certain applications.

The X6800 is the dual Core 2 Extreme part. Clock parity of quad-core with this dual-core chip answers “any performance advantage the higher clocked X6800 had when running single-threaded applications”.

In most other situations, the quad will simply perform better. It’s got four cores.

You can read more about the new processor if you want. “Just hide your tax return”.

That’s assuming you have a tax return.

Dual-core is still better in some applications, at some settings, but differences are in the noise.

One test the Core 2 Extreme QX6800 did not win was the one for power consumption. This test is won by who uses the least power, not who draws the most.

Like other Core 2 chips, the energy efficiency of the chip shines under load, rather than at idle.

Though it has two times the number of cores, it isn’t two times as fast. Nevertheless, about the only drawbacks are price ($1,200) and power draw.

A new king of the hill has arrive.

Hot Hardware

In the past, the name of the game was to see “who has the highest clock speed” (Introduction). Now the game’s multi-core.

AnandTech has benchmarked the Xeon 5300, or Clovertown, family of CPUs. “Virtualization is the primary target for Clovertown” (Intro).

Virtualization allows various operating systems to run within their very own virtual machines on a single CPU. Multiple cores can handle multiple virtual machines, one per core, though virtual machines can also span single cores as well.

A senior technical rep at an IBM conference in 2006 said that in “the coming years, the operating systems we use today will be merely applications” (Intro).

Multicore is accelerating the trend toward virtualization. “Virtualization is growing at an exponential rate” (Intro).

Quad-core offers twice the processing power of dual, which is good. However, one must be careful lest the I/O subsystem become a bottleneck.

In 6-9 months, AMD’s native quad-core Barcelona and Intel’s Penryn families of processors will be upon us, making these benchmarks of less interest.

Intel’s quad-core Penryn cache is fixed at 12MB. However, Intel has not disclosed the processor speeds of Penryn. Possibly the reason is that Intel is waiting on AMD to release Barcelona, so Intel can better measure how high it needs to clock its next-generation CPUs in order to stay competitive, or even beat the competition.

Intel’s 45nm process technology leaks less current, which enables Intel to clock its chips higher without generating additional heat. The chips may generate less heat, but they will not generate more. The amount of heat can be controlled by how fast the chips are set to run.

AMD says that its native quad-core will be faster clock for clock. However, given the higher-clocked Penryn chips, “AMD will apparently need to be about 40% faster clock for clock” (Conclusion).

That, by the way, is about how much AMD claims Barcelona will outperform Clovertown.

Source: AnandTech: Intel Clovertown: Quad Core for the Masses: Introduction, Conclusion