Overclocking is the practice of making computer components operate beyond their stock performance levels by manipulating the frequencies at which the component is set to run, and, when necessary, modifying the voltage sent to the component to allow it to operate at these higher frequencies more stably. In newer systems, the PCI, AGP, and PCI Express peripheral buses often receive their own clock signals, which eliminates their dependence on the front-side bus for timing. In older systems, these buses are operated at a set fraction of the front-side bus frequency.
Similar to the memory bus, the PCI and AGP buses can also be run asynchronously from the front-side bus. However, if the computations involving each element are more complex, the processor will spend longer performing these therefore, the FSB will be able to keep pace because the rate at which the memory is accessed is reduced. A slow FSB will cause the CPU to spend significant amounts of time waiting for data to arrive from system memory. In image, audio, video, gaming, FPGA synthesis and scientific applications that perform a small amount of work on each element of a large data set, FSB speed becomes a major performance issue. Due to differences in CPU and system architecture, overall system performance can vary in unexpected ways with different FSB-to-memory ratios. This is often referred to as an 'asynchronous' system. The memory will run 5/4 times as fast as the FSB in this situation, meaning a 400 MHz bus can run with the memory at 500 MHz. In newer systems, it is possible to see memory ratios of "4:5" and the like. Increasing the front-side bus to 450 MHz in most cases also means running the memory at 450 MHz. Often, these two buses must operate at the same frequency.
The memory bus connects the northbridge and RAM, just as the front-side bus connects the CPU and northbridge. Setting an FSB speed is related directly to the speed grade of memory a system must use. The first example was field-programmable gate array (FPGA) co-processors, a result of collaboration between Intel- Xilinx- Nallatech and Intel- Altera-XtremeData (which shipped in 2008). Prior to this announcement, made in Spring 2007 at Intel Developer Forum in Beijing, Intel had very closely guarded who had access to the FSB, only allowing Intel processors in the CPU socket. In response to AMD's Torrenza initiative, Intel opened its FSB CPU socket to third party devices. These secondary system buses usually run at speeds derived from the front-side bus clock, but are not necessarily synchronized to it. Other buses like the Peripheral Component Interconnect (PCI), Accelerated Graphics Port (AGP), and memory buses all connect to the chipset in order for data to flow between the connected devices. The FSB design was a performance improvement over the single system bus designs of the previous decades, but these front-side buses are sometimes referred to as the "system bus."įront-side buses usually connect the CPU and the rest of the hardware via a chipset, which Intel implemented as a northbridge and a southbridge. They are seldom used in embedded systems or similar small computers.
Ī front-side bus (FSB) is mostly used on PC-related motherboards (including personal computers and servers). "Front side" refers to the external interface from the processor to the rest of the computer system, as opposed to the back side, where the back-side bus connects the cache (and potentially other CPUs).
#PROCESSOR FOR FSB 1333 MOTHERBOARD PRO#
The term came into use by Intel Corporation about the time the Pentium Pro and Pentium II products were announced, in the 1990s.