64 bit

In computer architecture, 64-bit integers, memory addresses, or other data units are those that are 64 bits wide. Also, 64-bit CPUs and ALUs are those that are based on processor registers, address buses, or data buses of that size. A computer that uses such a processor is a 64-bit computer.
From the software perspective, 64-bit computing means the use of machine code with 64-bit virtual memory addresses. However, not all 64-bit instruction sets support full 64-bit virtual memory addresses; x86-64 and ARMv8, for example, support only 48 bits of virtual address, with the remaining 16 bits of the virtual address required to be all 0's or all 1's, and several 64-bit instruction sets support fewer than 64 bits of physical memory address.
The term 64-bit also describes a generation of computers in which 64-bit processors are the norm. 64 bits is a word size that defines certain classes of computer architecture, buses, memory, and CPUs and, by extension, the software that runs on them. 64-bit CPUs have been used in supercomputers since the 1970s (Cray-1, 1975) and in reduced instruction set computers (RISC) based workstations and servers since the early 1990s. In 2003, 64-bit CPUs were introduced to the mainstream PC market in the form of x86-64 processors and the PowerPC G5.
A 64-bit register can hold any of 264 (over 18 quintillion or 1.8×1019) different values. The range of integer values that can be stored in 64 bits depends on the integer representation used. With the two most common representations, the range is 0 through 18,446,744,073,709,551,615 (264 − 1) for representation as an (unsigned) binary number, and −9,223,372,036,854,775,808 (−263) through 9,223,372,036,854,775,807 (263 − 1) for representation as two's complement. Hence, a processor with 64-bit memory addresses can directly access 264 bytes (16 exbibytes or EiB) of byte-addressable memory.
With no further qualification, a 64-bit computer architecture generally has integer and addressing registers that are 64 bits wide, allowing direct support for 64-bit data types and addresses. However, a CPU might have external data buses or address buses with different sizes from the registers, even larger (the 32-bit Pentium had a 64-bit data bus, for instance).

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  1. D

    Help Windows 10 i5-2410M

    Hello po mga boss. Patanong lang po sana, May gamit po akong laptop na i5-2410m 2.30Ghz Windows 10 64bit po naka install na OS pagka bili ko and ma lag po sya, Nag try din po ako mag instaall ng different na version ng Windows 10 pero ang lag po talaga ng interface nya. Ano po kayang compatible...
  2. K

    Help New format

    Mga master .. new format desktop pc po.. ano po mga magandang ilagay na antivirus? Or mga pc apps? Tia..
  3. S

    Help Difference between 32 bit and 64 bit os.?

    hi! tatanong lang ako, anong pinagkaiba nila (maliban sa num) at saka anung mangyayari once na nag upgrade ako ng 64bit??
  4. H

    Help Ano po magandang pang edit sa video gamit ang windows7 64bit

    patulong naman po. tapos pa link na rin po kung meron man, salamat po
  5. T

    Help Need brightness and contrast adjust software for windows 7

    Pa tulong mga paps. Kailangan ko kasi ng software na makakapagadjust ng brightness at contrast sa pc win7 64bit baka meron kayong alam na magandang software. mas okay din if gagana agad sa start-up. Thanks in advance pag may mkakatulong. Nasira kasi menu buttons sa monitor ko eh. :):):)
  6. J

    Help [Question] about 32 bit (86x) and 64 bit (x64)

    Paano po gawing 64 bit ang pc kong 32 bit?