Advanced Micro Devices Inc. on Tuesday released the first 64-bit Athlon processors to use its “Socket 939” interface. Offering gains in HyperTransport performance, the updated chip comes with a new chipset and a substantial price delta over previous chips.
AMD introduced four new processors: a new 939-pin variant of its Athlon FX family, the Athlon 64 FX-53; and three new Athlon 64 chips, the 3800+, 3700+ and 3500+. Although AMDs “model numbers” imply a consistent architecture, the opposite is true. All four vary in the number of pins used, as well as the cache size and width of the memory bus.
Since AMDs Athlon 64 and Opteron architecture include an integrated memory controller, the company often redesigns the entire chip to enable faster memory speeds.
For example, two of the new chips, the Athlon 64 3500+ and 3800+, feature the new Socket 939 infrastructure, which intrinsically supports a 128-bit-wide memory interface to unbuffered DDR400 memory.
However, AMDs other introduction, the Athlon 64 3700+, uses the conventional Socket 74 interface used by the older Athlon 64 chips and a 64-bit memory interface. At the same time, both the 3500+ and 3800+ Socket 939 chips contain just 512 Kbytes of cache, while the new Socket 754 3700+ attempts to make up for the slower memory interface with a larger 1MB cache.
In addition, AMD has increased the speed of the Socket 940s HyperTransport interface, the point-to-point connection that ties the AMD processor to the rest of the system. Previously, the HyperTransport link operated an effective rate of 800MHz; now, AMD has increased the effective speed to a full gigahertz. Chipset partner Via Technologies Inc. announced that its K8T800 Pro chipset will support AMDs new HyperTransport speed. Motherboards using the new chipset will be available in “early June”, according to the company.
All of the new chips run at an actual clock speed of 2.4 GHz, save for the Athlon 64 3400+, which runs at the 2.2-GHz used by AMDss most recent chips.
|Name||Socket||Memory Interface||Speed||L2 cache size|
|Athlon 64 FX-53||939||128-bit||2.4GHz||1MB|
|Athlon 64 FX-53||940||128-bit registered||2.4GHz||1MB|
|Athlon 64 FX-51||940||128-bit registered||2.2GHz||1MB|
|Athlon 64 3800+||939||128-bit||2.4GHz||512KB|
|Athlon 64 3700+||754||64-bit||2.4GHz||1MB|
|Athlon 64 3500+||939||128-bit||2.2GHz||512MB|
|Athlon 64 3400+||754||64-bit||2.2GHz||1MB|
|Athlon 64 3200+||754||64-bit||2.0GHz||1MB|
|Athlon 64 3000+||754||64-bit||2.0GHz||512MB|
So far, AMD has not provided any means of differentiating between the two infrastructures. Intel, on the other hand, has used processor “suffixes”, such as the Pentium III “EB”, to indicate a change in manufacturing and cache size.