In a computer all bytes in the memory system need a unique name. This is called an address. For example, if you have 2 GB of main memory, then there are 2147483648 bytes of RAM in your machine, each of which require an address for the operating system to communicate to it. To give these all an address you need 31 bits to do it. Now, if/when you have 32 bits, you can name 4 GB (2 bytes to the 32nd power = 4GB).
This is why the total addressable space available in a 32 bit OS is 4GB – the OS runs out of addresses and cannot communicate/locate any more bytes of memory because of that.
You may think ”Hey, 4GB of address space… 4GB of RAM… What’s the problem” The problem is that memory isn’t the only thing needing an address. If you install a total of 4GB worth of RAM, the system will detect/use/display less than 4GB of total memory because of address space allocation for other critical functions, such as:
- System BIOS (including motherboard, add-on cards, etc..)
- Motherboards resources
- Memory mapped I/O
- Configuration for AGP/PCI-Ex/PCI
- Other memory allocations for PCI devices
Different onboard devices and different add-on cards (devices) will result of different total memory size. e.g. more PCI cards installed will require more memory resources, resulting of less memory free for other uses.
This limitation applies to most chipsets & Windows XP/Vista 32-bit version operating systems. Again, this is a limitation of the Operating System not having enough address space to allocate to the system *and* the RAM. Not allocating address space to devices renders them inoperable. Not allocating addresses to RAM simply results in the unaddressed section not being used in an otherwise fully functional computer. Therefore the OS designers assign RAM last.
If you install a Windows operating system, and if more than 3GB memory is required for your system, then the below conditions must be met:
1. A memory controller which supports memory swap functionality is used. The latest chipsets like Intel 975X, 955X, Nvidia NF4 SLI Intel Edition, Nvidia NF4 SLI X16, AMD K8 and newer architectures can support the memory swap function.
2. Installation of Windows XP Pro X64 Ed. (64-bit), Windows Vista 64, or other OS which can provide more than 4GB worth of address space.
Note: Windows Vista 32bit SP1 and newer (Win 7) will display the installed amount of RAM. This is a display change only.
i think Scottq gave an excellent answer. How does RAM relate to performance?
i was writing you a detailed explanation but i got tired of figuring out how far of an explanation you will need, seems like you just want to know yes or no.
so if ur question is about running a 32bit os on a 64bit hardware then all your cpu registeres will be 50% under utilized. so then the answer is
No performance drop comparing to another 32bit system with similar memory configuration. even you installed a 64bit OS but only have 4gigs of ram you will not see much benefit of the 64bits unless of course your running programs that would calculate on long long, double, and floating point arithmetic with high precession.
to summarize the 32/64 bit change mainly are for higher memory access and large/precision calculations.
if performance means something else to you then investigate on better disk io options.
because anytime where your asking your operating system to do a job while the available physical memory (RAM) is already utilized with currently running tasks or idle threads it must utilize pagefile/swap space to be able to move memory between your physical memory and virtual memory.
and the way to make that swaping operations faster is with faster disk IO and some advance partitioning/relocating
Man, I got confused. I only asked if it will reduce the performence of my CPU, I didn't asked about the RAM.
Will it reduce the performence, yes or no?
The CPU will perform as it should in a 32bit enviroment. But the real answer to your question is yes. 64bit not only can address more memory overall, it is more efficient. I have installed multiple OSes and everytime I do 64bit, its faster. Windows 7 64bits SP1 is faster than the 32bit SP1. Any program that has 32bit and 64bit installers, the 64bit installer will normally install almost 2x faster.
And from what scottq said, his post has very relivant information. A OS with more accessable RAM will also perform better. If you have 8GB for example, on a 64 bit OS you can disable virtual memory which uses a HDD which is a major bottleneck and will have a nice performance increase. But on a 32bit system, you can only address up to 4GB total and in most cases physical RAM can only use about 3.25-3.5GB total out of 4GB.
If you are going for Windows 7, go for 64bit. As a added bonus, Windows 7 64bit has a feater called KPP, Kernal Patch Protection. Basically it is a feature that does not allow for programs to directly access and modify the kernal. This means that viruses have no way of completley destroying the OS. In fact, every 64bit 7 install I remove viruses from survives while most 32bit OS installs get majorly damaged.
I have the i5-750 and it's a 64-bit processor.
My question is that if I have 32-bit os, will it reduce the performance of my CPU?
The only thing I know is that 32-bit op's can read maximum 3.12GB RAM, and when it comes to CPU's I know nothing.
Nope:-) U'll get 100% performance out of ur chip, because its actually an x86-64 bit processor [link]http://en.wikipedia.org/wiki/X86-64[/link].
The 64bit may be microscopically slow, or fast depending on what software is running. Also , some 64 bit applications use more RAM, so if ur using a 32bit OS, getting say 3.2GB or 3.5GB ram, or a 64bit with full 4GB, i doubt you'll notice any difference. But yes, more than 4gb, or if u wanna add more RAM later,then definitely 64bit.
PS:- Not to confuse you, but, ur processor is really a 32bit one, which emulates 64bit to the OS :-) All processors, except Itaniums are not true 64 bit, but don't break ur head over this:-)
often with less resorces used you will get slightly better real world performance from a 32bit o.s this isnt because your cpu is working more efficiently because the opposite is true. its purely down to the system requirements and overhead not being as great.
so yes in essence using a 32bit o.s when you have less than 4gigs of total ram will enable better system performance over all.
personally i recommend that every 1 with more than 3 or more gigs of ram should move up to a 64bit o.s. as system resources aint gonna be a problem.