AMD’s Barton core arrives, targets Pentium 4

The additional cache placed on the die of Advanced Micro Devices Inc.’s (AMD’s) new Barton core for its Athlon XP processors vaults the Athlon XP 3000+ ahead of rival Intel Corp.’s highest-performing processor, AMD said Monday.

The AMD Athlon XP 3000+, released Monday, now features 640KB of on-die cache, up from 384KB on the older Thoroughbred core, said John Crank, senior brand manager for the Athlon product line. Otherwise, the processor is identical to older Athlon XPs with a 333MHz front-side bus, Crank said.

In a presentation, AMD cited benchmarks that showed the 3000+ processor provided a higher level of performance than Intel’s 3.06GHz Pentium 4 processor, which features a technology known as hyperthreading. Those benchmarks also showed that Intel’s hyperthreading technology actually caused a four per cent decrease in performance compared to a 3.06GHz processor with hyperthreading turned off. Hyperthreading allows an operating system or application to believe a system has a second processor in addition to the actual chip, causing it to send more instructions to the processor.

Naturally, Intel defended its technology. “The Pentium 4 processor gives up to a 25 per cent performance improvement in multithreaded application scenarios,” said George Alfs, an Intel spokesperson.

“When a multiprocessor kernel is loaded, there can be a one to two per cent overhead (drag on performance), but that is more than made up for in a more responsive system when multitasking and running multithreaded applications,” he said.

Many users consult benchmarks to compare processor performance, but a benchmark only reflects the performance of that processor for the particular application on which it was tested. AMD used several 3D gaming benchmarks, including Unreal Tournament and QuakeIII, as well as Sysmark 2001, an office productivity and digital media benchmark developed by the Business Application Performance Corp. (BAPCo)

Illustrating the delicate nature of benchmarking results, AMD itself attacked the Sysmark 2002 benchmark last year, charging it was altered to favor Intel’s Pentium 4 processors. Since making those allegations, AMD has joined BAPCo, but at the time Sysmark 2002 was developed, Intel was the only desktop processor vendor involved in that standards-setting process.

AMD is expected to post the benchmarking results and the specifications of the systems used to obtain the results on its Web site Monday.

The Sunnyvale, Calif., company will extend the Barton core to its previously announced Athlon XP 2800+ processor. When the 2800+ was launched, it was only made available in a limited number of specialized gaming systems, and AMD will not manufacture any more of those 2800+ processors with the Thoroughbred core, Crank said.

The 2800+ with the Barton core runs with a slower clock speed than the 2800+ with the Thoroughbred core, allowing AMD to keep the same processor rating despite the increased cache, Crank said. AMD’s rating system is officially based on the performance of current processors relative to AMD’s original Athlon core, but the numbers mirror the clock speeds of competing processors from Intel.

The new Barton 2800+ runs at 2.083GHz, compared to the older 2800+ clock speed of 2.25GHz. The 3000+ runs at 2.167GHz.

A processor with the Barton core was supposed to launch in the fourth quarter of 2002, but was delayed last September. AMD also recently delayed the 64-bit Athlon64 desktop processor until later this year, saying that the Barton core will provide enough performance for the company to stay competitive until Microsoft Corp. delivers a 64-bit version of Windows XP for the x86 instruction set.

The 3000+ processor is available internationally in systems from NEC Computers Inc. Crank said Hewlett-Packard Co. is expected to develop a system with the 3000+ processor in coming weeks.

The chip is priced at US$588 in quantities of 1,000 units, compared to a price of US$637 for the 3.06GHz Pentium 4 processor in quantities of 1,000 units. With Monday’s announcement, the price of the 2800+ drops to US$375 from US$397.

AMD will launch an Athlon XP 3200+ with the Barton core around the middle of this year, Crank said.

Benchmark information provided by AMD can be found on its Web site at