AMD Athlon 64 & Athlon 64 FX - It's Judgment Day

Final Words

Seemingly overnight AMD went from about to fall off of the performance charts to being competitive with Intel's latest and greatest. But there's much more to this situation than proclaiming a winner and leaving it at that; AMD has lost a considerable amount of credibility, and the Athlon 64 (and FX) of today will not bring AMD back to the heydays of the Athlon.

For starters, at a 192mm^2, the Athlon 64 and Athlon 64 FX are well above AMD's "sweet spot" for manufacturing. When we last talked with AMD's Fred Weber, 100 - 120mm^2 die size is ideal for mass production given AMD's wafer size, yields and other manufacturing characteristics - and the Athlon 64 is close to twice that size. For the Athlon 64 to become the mainstream part that AMD wants it to be, they need to significantly reduce the die size - a shrink that the move to 90nm would be able to do just that. The mass market success of the Athlon 64 is directly dependent on AMD's ability to move to 90nm, until then the 64 will be exclusively a high-end part.

You can also understand AMD's desire to bring to market a 256KB L2 version of the Athlon 64, as reducing the cache size would not only cut down on the ~106M transistors but also significant die area.

AMD has also priced the Athlon 64 and Athlon 64 FX very much like the Pentium 4s they compete with, which is a mistake for a company that has lost so much credibility. AMD needed to significantly undercut Intel (but not as much as they did with the Athlon XP) in order to offer users a compelling reason to switch from Intel. However, given the incredible costs of production (SOI wafers are more expensive as well) and AMD's financial status, AMD had very little option with the pricing of their new chips.

When it comes down to recommendations, the Athlon 64 offers very compelling performance at a much more reasonable price point than the Athlon 64 FX. We cannot recommend the FX until AMD does release a version with unbuffered memory support and we would strongly suggest waiting until the Socket-939 version is released if you are considering the FX.

What is promising however are the performance gains we saw when recompiling for 64-bit on the Athlon 64; if AMD can actually get 64-bit applications and a compatible OS from Microsoft out in the market then the recommendations become much more positive for AMD. Until then, it's wait and see, AMD has done well but execution isn't a singular task - it is continued execution that will guarantee AMD a spot at the top of the market again.