Jump to 0 top | 1 navigation | 2 content | 3 extra information (sidebar) | 4 footer | 5 toolbar


Content

Megahertz myth

I had find many products about Herbal feed additive. Herbal feed additive KEQINLING is the Chinese natural galenical to promote poultry production and strengthen immunity performance for poultry, which developed by Guangdong VTR Bio-tech Co., Ltd. and Zhongshan University.It is a natural feed additive of herbal extract, screened out by a mass of experimentation on animals. Applied Object To prevent Avian Influenza, improve poultry's immunity and growth performance for poultry farm. IngredientsThis product contains various natural botanic efficacious contents, such as flavonoids, alkaloid, organic acid, polysaccharide, volatile oil. Product FunctionPrevent Avian Influenza During the chook experiment of artificial infecting high pathogenicity Avian Influenza virus strain H5N1, the death rate of the group without drug was 83.386.7%, the death rate of the group treated 2 KEQINLING was 13.323.3%, which substantial reduces the death rate by 7085% (p<0.01). KEQINLING can succeed protect poultry against AI by 76.786.7 %p<0.01, which was the great breakthrough in t

And you can see more from Cars The Game arcade crane games skins for psp hand play game tv casino game discount magnetic games marble top consoles ds lite nintendo match maker game
(Redirected from Megahertz Myth)
The megahertz myth, or less commonly the gigahertz myth, refers to the error of using clock rate to compare the performance of different microprocessors. While clock rates are a valid way of comparing the performance of different speeds of the same model and type of processor, other factors such as pipelines and instruction sets can greatly affect the performance when considering different processors. For example, one processor may take one clock cycle to add two numbers and another clock cycle to multiply by a third number, whereas another processor may do the same calculation in one clock cycle. Comparisons between different types of processors are difficult because performance varies depending on the type of task.
A benchmark is a better way of measuring and comparing computer performance.
Contents
1 Basis of the myth
2 Historical development
2.1 Background
2.2 Rise of the myth
2.3 The myth becomes counterproductive
3 References
4 External links
//
Basis of the myth
The myth arose because the clock speed was commonly taken as a simple measure of processor performance, and was promoted in advertising and by enthusiasts without taking into account other factors. The term came into widespread use (or was even originally coined) in the context of comparing PowerPC-based Apple Macintosh computers with Intel-based PCs. Marketing based on the myth led to the clock speed being given higher priority than actual performance, and led to AMD introducing model numbers giving a notional clock speed based on comparative performance to overcome a perceived deficiency in their actual clock speed.
For example, a processor at twice the clock speed may only accomplish half the number of instructions per cycle, thereby offering no more performance than the slower-clocked alternative.
Historical development
Background
The x86 CISC based CPU architecture which Intel introduced in 1978 was used as the standard for the DOS based IBM PC, and developments of it still continue to dominate the Microsoft Windows market. An IBM RISC based architecture was used for the PowerPC CPU which was released in 1992. In 1994 Apple Computer introduced Mac computers using these PPC CPUs, but IBM's intention to produce its own desktop computers using these chips was thwarted by delays in Windows NT and a falling out with Microsoft. Initially this architecture met hopes for performance, and different ranges of PPC CPUs were developed, often delivering different performances at the same clock speed. Similarly, at this time the Intel 80486 was selling alongside the Pentium which delivered almost twice the performance of the 80486 at the same clock speed.
Rise of the myth
Computer advertising emphasised processor megahertz, and by late 1997 rapidly increasing clock speeds enabled the Pentium II to surpass the PowerPC in performance. Apple then introduced Macs using the PowerPC G3 which they claimed outperformed Pentium IIs while consuming less power. They illustrated this with commercials showing a Pentium II on a snail, and a "Toasted Bunny"-suited character parodying Intel's commercials. Intel continued to promote their higher clock speed, and the Mac press frequently used the "megahertz myth" term to emphasise claims that Macs had the advantage in certain real world uses, particularly in laptops.
In November 2000 Intel's heavily advertised advances in clock speed reached an extreme with the release of the Pentium 4 which sacrificed per-cycle performance and used a deep instruction pipeline to gain higher clock speeds, ignoring problems that this introduced heat production and power consumption.
Comparisions between PowerPC and Pentium had become a staple of Apple presentations. At the New York Macworld Expo Keynote on July 18, 2001, Steve Jobs described an 867MHzG4 as completing a task in 45seconds while a 1.7GHzPentium4 took 82seconds for the same task, saying that "the name that we've given it is the megahertz myth". He then introduced senior hardware VP Jon Rubinstein who gave a tutorial describing how shorter pipelines gave better performance at half the clock speed.
AMD also produced x86 designs which competed with Intel on performance rather than price. In January 2002 the Pentium 4 gained a lead in sales and AMD marketing responded by giving their processors numeric suffixes approximating the clock rate that an AMD Thunderbird (and by inference a Pentium processor) would need to give matching performance, openly undermining the "megahertz myth".
The myth becomes counterproductive
The Pentium 4 was unsuitable for laptops due to its heat dissipation and power requirements, and in March 2003 Intel overcame these difficulties with the Pentium M, which proved capable of matching the Pentium 4 on performance at significantly lower clock rates. In...(and so on)

You can also see some feature products :

game boy micro usb game controllers ps2 8mb memory card strip poker game supplier nintendo wii wholesale supplier playstation fingerprint access controllers great game console tv game console flash player game handheld sudoku game Magnetic Chess Set network adapter ps2 virtual archery game multifunctional wii game discount computer games electronic chess games electronic game consoles wii board game dance tv game non electronic dartboard

  • No ratings
  • No ratings
  • No ratings
  • No ratings
  • No ratings
  • 0 ratings
Pages: 1 (1 - 1 / 1)