Interview with AMD's Fred Weber - The Future of AMD Microprocessors

An Update on Turion

We also managed to corner some AMD folks about their new "mobile technology", the Turion 64. Here's what we were able to get out of them:

Much as we suspected, all of the power optimizations that went "into" Turion 64 are all transistor level optimizations.  Basically, selecting transistors that provide better thermal and power characteristics at the expense of lower switching frequencies.  Given that the Turion 64 runs at multiple speed grades lower than the fastest desktop Athlon 64s, this trade-off makes sense, but it also means that Turion 64 is no Pentium M killer.  There was one logic level optimization that went into Turion 64 and that was the support of a deeper C3 sleep state, but other than that, the Turion 64 is architecturally identical to a Socket-754 Athlon 64. 

The similarity between mobile and desktop goes one step further as we just confirmed that the packaging of the Turion 64 is no different than the Socket-754 desktop Athlon 64, except for the fact that the heatspreader is removed.  AMD did mention that they are looking at different packaging options that would surface in the second revision of the Turion 64 microprocessor. 

The Turion 64 notebooks that are going to be released will all be in the 1" - 1.4" thickness range, and weigh around 5 to 6.5 lbs.  The Turion is specifically targeted at what AMD is referring to as the mainstream thin and light segment, which also means that AMD will continue to remain non-competitive in the smaller form factor notebooks in which Centrino is available. 

AMD did mention that there is "focus" on a new mobile platform architecture, presumably similar in approach to the Centrino platform, designed from the ground up to be specifically for mobile applications rather than just down-scaling desktop technologies.  AMD was extremely quiet about details on this front other than the fact that it was something that their new Japan engineering lab is playing a key role in defining.  Whenever this new architecture does surface, it will carry the Turion brand.

Final Words

From talking to people like Justin Rattner and Fred Weber, the future of the CPU industry is looking to be particularly bright.  For the first time in recent history, we have both AMD and Intel agreeing on major points of future microprocessor architectures, and to AMD's credit, it looks like a lot of the decisions they made with the Athlon 64 were, in fact, the right ones.  What can we expect from AMD going forward?

We can expect the K8 execution core to remain relatively unchanged. Its successor may be deeper pipelined, but for the most part, the core itself appears to be mostly done evolving. 

We can expect future AMD chips, beyond 65nm, to be large groupings of cores, but the focus will continue to be on making them all general purpose, however with varying individual strengths (symmetric and heterogeneous). 

The Cell approach appears to be one supported by both AMD and Intel, but also appears to be too early in both their eyes.  It's clear that giving up Weber's symmetric heterogeneous approach isn't a sacrifice that either AMD or Intel are willing to make; they both appear to be waiting for smaller manufacturing processes to approach architectures similar in nature to Cell without sacrificing present day performance or hardware transparency. 

We also asked Weber about his thoughts on wafer and die stacking; he sounded particularly interested in them, but added that for a microprocessor, it's far too early to count on die stacking because of yield concerns.  He said that the time for the technology to be used on microprocessors would only exist once there's mass market use of it in memory manufacturing. Then, and only then, would it be mature enough to migrate to microprocessors.