- What is a CPU?
- Tracing an instruction
- L1/L2/L3 Cache
- Clock cycle speed
- Front side bus (FSB)
- The numbers game: Intel vs AMD
- Sockets and slots
- Dual-core and quad-core CPUs
- 64-bit processors
- Mobile Processors
- Budget lines: Celeron, Sempron and Athlon
AMD was the first processor manufacturer to offer a 64-bit CPU with the launch of the Athlon 64 processor. However, the vendor was quick to point out that it's a technology that's suited to today's applications as well as any future 64-bit-only applications. Nowadays, almost all of AMD's CPUs are capable of processing 64-bit instructions, even CPUs in its Sempron range.
AMD's approach to 64-bit processing on the desktop has been a largely inclusive one, as its Athlon FX, Athlon 64 and Phenom CPU lines support multiple operating modes that will run 32-bit operating systems and applications, true 64-bit operating systems and applications and even 32-bit applications on 64-bit operating systems.
There's an element of future-proofing in buying a 64-bit processor, as you're readying yourself for software applications and hardware drivers that will be capable of running under a 64-bit operating system such as the 64-bit version of Windows Vista. Many 32-bit applications will run without any problems on the 64-bit version of Vista, but stability and compatibility is still an issue as drivers for many hardware components (wireless network cards, for example) still don't work properly under the 64-bit environment.
Athlon 64 vs Athlon 64 FX
AMD currently sells three differing types of 64-bit processor, aimed at different market segments and with somewhat different internal architecture and packaging. When initially launched, the Athlon 64 FX line was the premium brand version of the Athlon 64, with a dual channel memory controller built into the chip, double the L2 cache memory and a 939 pin socket. Newer Athlon 64 FX CPUs are built to an identical standard as Athlon 64 X2 CPUs though, using Socket AM2, with similar levels of cache and integrated dual channel memory controllers. AMD is keeping the FX line as premium chips primarily through higher clock speeds, and by keeping the clock multiplier on the FX line unlocked, which makes them a popular choice with overclockers.
AMD's 64-bit processors shine in the gaming arena, partly because of elements such as the CPU's memory controller being integrated onto the CPU itself, reducing memory latency, and also in single threaded games that can take advantage of the additional memory registers within the Athlon 64 X2 and Athlon 64 FX. A number of popular game engines have also been significantly rewritten to take advantage of a 64-bit processor.