SAN MATEO, Calif. -- In a bold attempt to leapfrog rival Intel Corp. in the performance race, Advanced Micro Devices on Tuesday (Sept. 23) formally introduced a family 64-bit processors for mainstream PCs that the company hopes will mark the beginning of the end for 32-bit computing.
To kick off its crusade, AMD introduced three Athlon64 processors targeting mainstream desktops, mobile systems and high-end game machines. The processor line comes five months after the company introduced Opteron, a 64-bit processor for servers and workstations. Both the Opteron and Athlon64 are based on the same microarchitecture, which includes an on-chip memory controller and sophisticated out-of-order execution and branch prediction capabilities.
Though 32-bit computing is unlikely to disappear any time soon, AMD is betting on wider availability of software for 64-bit processors. A number of software developers involved in the Athlon64 launch expressed an interest moving to 64 bit. Among them are Microsoft, which is expected to introduce a 64-bit version of Windows next year.
A chief advantage of moving to 64 bits is that it lets processors address more than 4 gigabytes of memory, which is beyond the capability of 32-bit systems. This "memory wall" diminishes the realism of computer graphics and makes it difficult to send high-bandwidth data such as video over wireless networks, said Fred Weber, AMD vice president and chief technology officer.
AMD also is betting that PC games will be among the first applications to make the switch. Since launching its first 32-bit Athlon, the company said its had considerable success wooing game enthusiasts to its camp. It sees Athlon64 as a way to build on that momentum.
To drive home the point, the company has introduced premium line of 64-bit processors under the AthlonFX brand. The line includes a large on-die cache memory and 128-bit interface to external DDR memory, features that should boost bandwidth to main memory while reducing latency.
In some ways AMD shares a common vision with Apple Computer, which launched its first 64-bit PowerPC systems for consumers earlier this year. That both companies have announced plans to pursue 64-bit computing for mainstream users "is proof that this is the right time," Weber said.
The transition to 64-bit computing could depend largely on trends in memory technology. Currently, the average desktop system has about 512 megabytes of DRAM. To get the most out of 64-bit processors, the total would need to increase to 2 gigabytes or more. Weber said he's confident that memory prices will continue to decline at a rates that will fuel more memory usage. "The biggest benefits come as memory prices go down," he said.
Still, 64-bit computing will be overkill for many office productivity tools, which could make it a tougher sell for business users and IT managers. Weber acknowledged that many applications won't need 64 bits, but added that market trends could bolster the case for more computing power. He cited evidence that the replacement cycle for PCs has increased to four years, which would give IT managers an incentive to switch to 64-bit earlier rather than later, Weber said.
Moreover, the company stressed that having 64-bit capability won't come at the expense of 32-bit performance. The company claims that the FX-51, for example, can outperform a 3.2-GHz Pentium 4 by 10 to 20 percent. But these benchmarks may soon have to be revisited when Intel introduces Prescott, which will be built on 90-nm process technology and feature an enhanced P4 architecture.
AMD's Athlon64 is manufactured using 130-nm design rules and makes use of silicon-on-insulator technology to boost transistor performance.