AMD Athlon XP 1600+ AX1600DMT3C is one of the good brands available over online stores such as MDofPC, a popular store to provide quality CPU products. All Athlon XP microprocessors had rated speed. According to AMD, the rated speed could be used to estimate processor's performance relative to Athlon Thunderbird processors. When compared to Pentium 4 Willamette processors, the XP's rated speed was about 200 to 300 MHz lower than the speed of equally performing Pentium 4. For example, this AMD Athlon XP 1600+ was comparable to Pentium 4 1.8 or 1.9 GHz processors, and it was not uncommon for the XP 1600+ to outperform Pentium 4 Willamette 2 GHz in some benchmarks. AMD Athlon XP processor family is the successor to the Athlon CPU family. Palomino, the first Athlon XP core, had a few improvements over the previous Athlon core: * Complete set of SSE instructions * Palomino core added a data prefect mechanism. * Increased the size of the Translation Look aside Buffer. All Athlon XP Palomino CPUs had 266 MHz bus speed, and were manufactured using 0.18 micron technology. Next revision of Athlon XP core, called Thoroughbred, was manufactured on newer 0.13 micron technology, and as a result, had smaller die size and lower power dissipation than the Palomino core. Bus speed of some Thoroughbred processors was increased to 333 MHz AMD Athlon XP 1800+ AX1800DMT3C is also a competitor of these Athlon series processors that supports splendid gaming experience to gamers and custom built computers worldwide. It has various important features like 1800 MHz (rated), 1533 MHz (real, 266 MHz bus speed, Staggered organic PGA (Socket A/Socket 462). Similarly, AMD Athlon XP 1800+ provides same functionality that resolves some minors by it s previous versions. AMD Athlon XP 2000+ is also fall into this series. In addition to regular clock frequency of 1800 MHz, it now provides 2000 MHz (rated), 1667 MHz (real), 266 MHz bus speed, staggered organic PGA (Socket A/Socket 462). Performance of Pentium 4 microprocessors was improved with the introduction of Northwood core. The Northwood core had twice as much L2 cache memory when compared to older Willamette core, as a result performance of the Northwood processors was better than that of Willamette CPUs, but still this was not sufficient to outrun Athlon XP 2000+. All above specified CPUs defines strong base for the custom built & Gaming PCs. This is very important characteristics which are to be considered before purchasing any of the custom pcs. There are many online stores like MDofPC that manufacturers advanced custom built systems online.