12Sep Advanced Micro Devices

Several clone microprocessors such as the 5*86 (X5), the 5*86(k5), the k6, the k6PLUS-3D, and K7 microprocessors are offered by Advanced Micro Devices(AMD). The x5 offers operational and pin compability with the Dx4. Its performance is equal to that of the Pentium and MMX processors. The K5 processor is compatible with the Pentium, and the K6 is compatible with MMX. Both the K5 and K6 models are Socket-7 compatible, enabling them to be used in conventional pentium and Pentium MMX system-board designs(with some small modifications). The K6 employs an extended 64kb L1 cache that doubles the internal cache size of pentium 2.

The K6PLUS-3D is operationally and performance compatible with the Pentium Pro, and the K7 is operationally and performance compatible with the Pentium 2. NextGen produced three processors that can perform at the same level as the P5(Nx586) and P54C (Nx686) Pentium devices. These devices uses proprietary pin-outs, however, so they are not compatible with other processors. Eventually NextGen was purchased by AMD and it’s designs were incorporated in the k6 design.

Two notable AMD processors are the Athlon and the Duron. The Athlon is Pentium 3 clone processor. It is also available in a proprietary SPGA Socket-A design that mimics the Intel socket 370 specification. The Socket-A specification employs a 462-pin ZIF socket and is only supported by two available chipsets.

Three versions of the Athlon processor have been introduced so far. The first is the K7 version that ran between 500 to 700 MHz. The K75 processors ran between 750 MHz and 1GHz. The Thunderbird version ran between 750 MHz to 1.2 GHz.

The Duron features processor speeds between 600 MHz and 800 MHz. It includes a 128 KB L1 cache and a 64 KB L2 cache. Like the newer celerons, the Duron is constructed using 0.18 micron IC manufacturing technology.