The Athlon 64 line is an important one for AMD, as it provides a high-end mainstream choice in their current desktop line. Price and performance are important to this market sector, and while the Athlon 64 FX-51 provides the latter, its high retail price makes it more of a niche product for true enthusiasts. The Athlon 64 is positioned more as an alternative to the desktop Pentium 4 line, and is expected to match up in terms of high-end framerates, while keeping the price competitive.
AMD has already pulled a fast one with their Athlon 64 3000+, which features the same core speed as the Athlon 64 3200+ model, but only half the L2 cache. This helps AMD compete at the lower-cost high-end, but now that we've got the newest Athlon 64 3400+ in house, we're back to the standard higher-clocked, higher-priced model. In fact, the clock speed of the Athlon 64 3400+ is encroaching into Athlon 64 FX-51 territory, and it will be interesting to see how actual performance stacks up.
The Athlon 64 3400+ is the newest AMD64 entrant, and joins the Athlon 64 3000+ and 3200+ in this high-end 64-bit desktop line. The overall architecture hasn't changed from the initial Athlon 64 3200+ release, and the Athlon 64 3400+ is simply a higher-clocked revision. This includes a 0.13-micron core, 128KB L1 and 1MB L2 cache levels, one 1.6 GHz HyperTransport link, and a 1.5V core voltage. Where things change is naturally in the core speed, and the Athlon 64 3400+ raises the bar to a full 2.2 GHz. This is 200 MHz higher than the Athlon 64 3200+ (and the 512KB L2 Athlon 64 3000+ model) and on par with the Athlon 64 FX-51. Where these two 2.2 GHz processor diverge is with the integrated memory controller, which is single-channel DDR with the standard Athlon 64 3400+ and dual-channel for Athlon 64 FX models.
The Athlon 64 3400+ supports the Socket 754 processor package, and as with previous AMD64 models, sports an integrated heat spreader. The 2.2 GHz core speed and integrated single-channel memory controller also translates into a 2.2 GHz memory-to-controller speed. This faster memory bus is one of design wins that AMD receives from the integrated Northbridge functions of the Athlon 64, while having to contend with architectural challenges when supporting new memory types such as DDR-II. And last but not least, the newest AMD processor keeps up with the Intel crowd by supporting 3DNow! Professional/SSE2 instructions.
The Athlon 64 is still a relatively new processor design, and since we built the reference system from the ground up, we're presenting our thoughts. First off, the integrated heat spreader is a godsend, as you don't need to worry about cracking the core, and the surface area has been greatly increased. This provides a larger surface link between the CPU and heatsink-fan, and obviously makes installation far less stressful. This "open core" design was one of the main complaints from the Intel fans, and right now, both Athlon 64 and Pentium 4 processors are virtually equivalent in this area.
The Athlon 64 heatsink design is also quite good and is a huge improvement over the previous Athlon XP mode. The motherboard apparatus is similar to the Intel Socket 478 design, with an outer plastic mount and plastic tabs, which are attached to the heatsink fan's pressure tabs. Then a small plastic pressure clip is used to firmly attach the heatsink fan, and the job is done. This is actually an improvement on the standard Pentium 4 heatsink fan assembly, but not quite as seamless as some of the Socket 478 3rd-party HSF designs. We're waiting to see what some manufacturers comes up with in terms of Athlon 64 cooling, now that AMD has provided an integrated heat spreader and high-end mounting solution.