AMD takes aim at Intel

AMD Inc. says its newest chip, the AMD-K6-III, will takes its business into the heart of the commercial market and directly into prime Intel Pentium III territory.

According to Lance Smith, director of enterprise segment marketing for the Sunnyvale, Calif.-based organization, knowing that AMD has the technology to compete with Intel is not a problem — AMD is sure it has that. Imparting that knowledge to others is the challenge.

“Our biggest challenge is to get past ‘Who’s AMD?’ We have to get exposure in the commercial marketplace so we can get the success stories started,” he said.

“We have the OEMs, we have the product with the performance, we have the background and a history of selling large volumes of products into the commercial marketplace. We have many pieces of the puzzle, but the last one is getting ourselves exposure in the commercial marketplace.”

In order to do that AMD is willing to talk – about its processors, its competitor’s processors, and about the theory and practice of microprocessor design.

For starters, though, Smith wanted to talk about how AMD’s chip ranks against the better known Pentium products.

“We’re definitely going after the Pentium III with the K6-III. Performance-wise this is definitely possible. With the K6-III’s TriLevel cache, we’ve really opened up the core. You could say the K6 and the K6-II were limited by memory bandwidth, but with the backside Level 2 cache we have effectively bypassed the performance of the Pentium II and Pentium III.

The K6-III has a 64KB split-level, Level 1 cache, with 32KB devoted to handling data and 32KB for the instructions. The Level 2 has 256KB of full speed, burst-timing cache architected in a four-way set associative manner. The L2’s timing falls into a 3-1-1-1 cycle which adds up to a total of six clocks. Using the front side bus on its Super7 bus (which evolved from the Socket7 Pentium bus design), the K6-III can add 512KB, 1MB or 2MB of third-level cache.

The 0.25 micron K6-III is manufactured with a process that melts the five metal layers onto the ceramic package, and not the traditional wire bonding method, according to Smith. He said that allows AMD to place the grounds across the entire surface of the dye rather than just around the perimeter, which increases I/O performance, creates faster and more reliable parts and provides better electrical characteristics. He added that the chip’s transistors are actually connected in what is called the first metal layer (also called layer 0 or local interconnect), which improves the performance of the memory arrays.

In addition, Smith explained that the K6-III’s “execution pipeline is very different than the Pentium’s. The Pentium III core has a very deep, 14-stage pipeline. K6 has a six-stage pipeline. The one that is shorter will be able to start executing faster than the one that is longer. But one of the limitations of the design is that it is harder to get frequency out of a pipeline that is short. That’s why the Pentium III is 50MHz faster than the K6 right now. Over time that can be overcome.”

In addition to physical design differences, the K6-III uses different single instruction multiple data (SIMD) floating point instruction than Intel’s Streaming SIMD Extensions (SSE – formerly code-named KNI). AMD’s 3DNow instruction set was first introduced nine months ago on the K6-II, and has since garnered a lot of support from ISVs, especially game manufacturers. While AMD is now targeting business application developers, many of whom are now working to support SSE, Smith said that neither company will really be left out.

“Once you’ve organized the code for your application to deal with a SIMD floating point instruction, it makes no difference whether it is KNI or 3DNow. If you support one, it is very easy to support the other.”

Smith also said as long as developers write to standards such as OpenGL and DirectX, both the 3DNow and SSE instruction sets will work. Still, Smith cautions that in creating SSE, Intel has introduced brand new registers which he claims can “break” older operating systems that are unaware of the changes.

Gregory Weiss, a research analyst with D. H. Brown Associates Inc. in Port Chester, N.Y., sees the Intel design differently.

“It is true that the Pentium III instructions introduce what is called extra state – so when you switch between two applications like Word and Excel, it saves all of the information [from one and restores information to the other]. That operation means there is a lot of context switching. It is also true that with the Pentium III, [this operation] is a little less backward compatible than AMD’s instructions, so Intel needs to add things to the operating systems which take advantage of the new instructions.”

He concluded that inserting these patches won’t be much of a problem, because they can be added “under the covers” when the SIMD-based applications are loaded.

Even if Intel chips come with a few inherent problems, that won’t stop corporate buyers from using them, and they will never be serious enough to give AMD a good foothold in the commercial market,” said Rob Enderle, vice-president, at the Giga Information Group in Santa Clara, Calif.

“This product looks like it could perform in the corporate market, but it doesn’t have the kind of things a corporate buyer typically likes to see in a system: the remote management capabilities, and the robustness of system design. It is a good gaming machine.”