Implication of 64-bit processors
64-bit processors are at today's very high end, and they showcase all the best thinking in microprocessor design. This is the cutting edge, where silicon manufacturing, computer architecture, compiler technology, and marketing wizardry all come together.
(http://www.extremetech.com/article2/0,3973,231,00.asp)
To the normal desktop computer user, the implications of 64-bit computing aren’t that obvious. This is because the amount of data processed isn’t that great to demand such high computing power. The main implications are directly for high-end sector like web servers, huge databases (as in research and weather forecasting) and corporate applications. To further deter the normal user, prices of such processors are extremely high. As computer applications evolve, and extremely memory intensive applications like streaming TV/video, voice recognition and others become available to the normal desktop user, the question of 64-bit processors to support them will be in place, but for now 64-bit processors for desktops is a little farther away.
It's not that people don't want faster computers, they just don't want to pay much for them, which is another way of saying there's no compelling need. Processor speed and capacity continue to climb but for most applications, the gain in productivity doesn't increase nearly as much. Many applications targeted for 64-bit processors, such as very large databases, are hardly relevant to desktop computing, and some that might be, such as multimedia, are often handled by specialized processors (DSPs for sound, video, etc.).
We're accustomed to the idea of processor speed, traditionally measured in megahertz (MHz) and now gigahertz (GHz). This has some value as a relative measure of processor capacity, but it's misleading with 64-bit processors. The MHz rating of a processor tells you how many cycles ("ticks of the clock") it can perform in a second, but it doesn't indicate what it can do in each cycle. That's where the bit capacity comes in. A 64-bit computer can handle more computations, memory, and input/output with each processor cycle. That's why current 64-bit processors--such as the Intel Itanium, which runs at only 733 MHz--can be a more powerful processor than the current Pentium IV, which runs at 2.2GHz.
Unfortunately, there's a catch to using this power--software. Intel and AMD 64-bit processors are backward compatible with current 32-bit software, but using them that way is a waste. Software must be rebuilt with 64-bit compilers and, more realistically, redesigned for 64-bit operations. This includes the operating system. Consequently, the shift to 64-bit processors is a major change, not only in hardware but also in software.
What distinguishes 64-bit computing in the minds of designers, manufacturers, and typical users is its association with large-scale computing (huge databases, corporate applications) or very intensive computing (professional workstations). This level of computing is IT territory with procedures and attitudes that are far more systematic than the chaos of typical consumer use. The capability to accommodate huge quantities of memory, combined with their far greater efficiency at managing high-bandwidth I/O, give 64-bit systems scalability advantages that 32-bit technology can't match.
(http://archive.infoworld.com/articles/fe/xml/02/02/04/020204feintel.xml)
There are obviously other 64-bit processors that exist today but a major issue, which impacts their use, is the operating systems that support 64-bit PCs. Today, Windows 95 and Windows 98 do not support 64-bit computing and Windows NT provides only limited support on a special compiled version for workstations.
(http://www.mmsonline.com/articles/0998cim.html)
Eventually, either a hot application will come along to drive the change to 64-bit computers for the average user, or else the manufacturers of 64-bit hardware and software will simply throw products into the personal-computer market (via computer manufacturers) and let declining prices and the march of progress carry them along. Voice recognition might be the killer application, or maybe it'll be streaming media--but now nobody knows. For the time being, the mystery of the missing 64-bit computer is relatively simple: they will be much too expensive.
(http://www.computeruser.com/articles/2107,3,6,2,0701,02.html)
(http://www.sysopt.com/articles/64bit/index3.html)
Driving needs for 64-bit processors
The 64-bit processor provides a lot more space to handle data and complete complex calculations. On 32-bit chips like the Intel Pentium, some data must be pushed off the chip to accomplish incoming requests, which makes the computer slower at certain tasks as the chip shuffles data back and forth to get everything done.
So applications that require heavy calculations and data movement, such as data warehouses, 3-D modeling, scientific formulas, high-resolution graphics and transaction processing, can be hindered when run on 32-bit processors.
Internet-based technologies, including video streaming, voice traffic and movies, which require huge chunks of processing time, have also been driving the need for 64-bit processors on Internet servers.
The 64-bit chip promises to help in this regard because the amount of space that's available isn't just twice as much as the space on a 32-bit chip, it's also an order of magnitude higher — well beyond the needs of desktop applications these days. For example, Intel says the IA-64 processor it's currently developing includes eight times as many registers as a typical Pentium chip, and a typical 64-bit file can be up to 4 billion times larger than a 32-bit file.
That's a lot of data to have readily accessible in the main memory of the processor. As a result, the processor doesn't have to call out to other areas of computer memory to get information or go get the information from the slowest locations — hard and floppy disk drives.
But because all this extra room will only be used if operating systems and software applications are developed to run on 64-bit systems, most 64-bit chips will find their way into large servers, not desktops. One reason is that many versions of the Unix operating system that run on large servers are already made to run on 64-bit processors. But Windows and its applications aren't yet 64-bit ready.
(http://www.computerworld.com/hardwaretopics/hardware/desktops/story/0,10801,43533,00.html)
Recent efforts, such as Microsoft Corp.'s push toward having computers operate as TV/stereo players, underscore the need for 64-bit chips. That kind of consumer software is really going to start choking [32-bit- based] systems when they try to handle high-definition TV data as well as music, basically forcing the processor to try to handle eight times as much data at once,
(http://www.eweek.com/article2/0,3959,642927,00.asp)
Case study of possible use in image processing
Advantages:
- Massively reduced banding
- More accurate rendition of sub-pixel brushes
- Finer color correction
- Improved anti-aliasing and scaling
- Improved compositing
Disadvantages:
- Greater memory requirements in some cases
- Slightly slower performance
- Fewer suitable input and output devices than 32 bit
Basic Facts
Most 64-bit chips on the market today are targeted at high-end server uses. The chipmakers usually tweak the processor to work best with their own servers and operating systems to get the best performance out of the applications. Most of these vendors have been shipping 64-bit processors for two years.
But the legions of desktop users are another matter.
Typical desktop applications simply don't need the power of 64-bit computing and would leave all the extra space on a 64-bit processor sitting idle.
In other words, throwing your copy of Microsoft Corp.'s Office or Lotus 1-2-3 onto a 64-bit processor wouldn't result in any performance gains at all — at least until those applications become so huge and complex that they need 64-bit technology to excel.
(http://www.computerworld.com/hardwaretopics/hardware/desktops/story/0,10801,43533,00.html)
Reference: A summary of all the sites used.
(http://search390.techtarget.com/sDefinition/0,,sid10_gci498697,00.html)
(http://www.extremetech.com/article2/0,3973,231,00.asp)
(http://h21007.www2.hp.com/dspp/tech/tech_TechDocumentDetailPage_IDX/1,1701,937,00.html)
(http://astlor.ca/Astlor/64.htm)
(http://www.extremetech.com/article2/0,3973,231,00.asp)
(http://archive.infoworld.com/articles/fe/xml/02/02/04/020204feintel.xml)
(http://www.computeruser.com/articles/2107,3,6,2,0701,02.html)
(http://www.sysopt.com/articles/64bit/index3.html)
(http://www.computerworld.com/hardwaretopics/hardware/desktops/story/0,10801,43533,00.html)
(http://www.mmsonline.com/articles/0998cim.html)
http://www.amd.com/us-en/Processors/ProductInformation/0,,30_118_4699_7980,00.html
http://www.amd.com/us-en/Processors/ProductInformation/0,,30_118_4699_7981,00.html
http://www.extremetech.com/article2/0,3973,77735,00.asp