Windows 7 Is Here, BUT


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clifford_cooley

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And, that it's only 32-bit windows that has the 4GB memory limit
It's not a windows limit, It's math

1Bit = 2 addresses
2Bit = 4 addresses
16Bit = 65,536 addresses

32Bit = (4,294,967,296 Bytes) = (4,194,304 KiB) = (4,096 MiB) = (4 GiB)

64Bit = (18,446,744,073,709,551,616 Bytes) = (17,179,869,184 GiB) = (16,777,216 TiB)
 
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As an electrician, I'm quite familiar with math, thanks.
Would you care to vector some 3-phase power factors?

None of the Server 2003 or Server 2008 editions listed in wikipedia's page about PAE are actually 32-bit.
Refer to http://www.microsoft.com/windowsserver2008/en/us/pricing.aspx and you'll see there are no 32-bit versions of Server 2008 Standard/Enterprise/Datacenter offered.

Meanwhile, any (free) 32-bit Linux kernel starting with v2.3.23, and a CPU that supports it, can address up to 64GB of memory using PAE.
 

clifford_cooley

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Physical Address Extension
x86 processor hardware architecture is augmented with additional address lines used to select the additional memory, so physical address size is increased from 32 bits to 36 bits
Read more - Wikipedia, the free encyclopedia

This is all I have been saying all along. If you use PAE then you are increasing the number of bits from 32 to 36. And paging is a slower process that will not speed up your computer when it is reading and writing to Hard Drive. This is what is happening is it not?
 
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It's paged just like the first 4GB are paged without PAE, not like expanded memory nor like swap files.

It's directly addressing up to 68,719,476,735 bytes of RAM, and each 32-bit application can use up to 4GiB of that 64GiB.
 
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clifford_cooley

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The only way to extend memory is to add memory or use a different resource such as a hard drive. You keep talking as if PAE can store 64GB withing 4GB. That is not possible.

This conversation is closed because we have been way off topic.
 
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You are right Clifford, swapping to A HDD is exactly what it does.

Darr247 is right about how much memory it access, but it would be much slower than actual RAM, since it swaps contents of RAM to a HDD which frees up the same RAM to be used again.
 
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You are right Clifford, swapping to A HDD is exactly what it does.

Darr247 is right about how much memory it access, but it would be much slower than actual RAM, since it swaps contents of RAM to a HDD which frees up the same RAM to be used again.

Ahhh... so THAT's why win7 is so slow - because it's constantly swapping to disk all the time.
 

clifford_cooley

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Darr247

My argument was if you include the page file then Windows does not have a 4GB limit either.

If you drop the paging then linux and windows both have the 4GB memory limit.
 
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Win 7 is far faster on my PC than Vista or XP ever was, only Linux was faster.

Technically, Windows 32 bit is limited to 3 GB, Linux 3.2 - 3.6 GB
 
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Darr247

My argument was if you include the page file then Windows does not have a 4GB limit either.

If you drop the paging then linux and windows both have the 4GB memory limit.

If you two think the 'page structures' used to address RAM has anything to do with swap files, you're completely misunderstanding how it works.

PAE has nothing to do with swap files; I suggest you go reread the article at the 'read more' link you cited.
 

clifford_cooley

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Whether its paging or not it is still writing to Hard Drive and is handicapped by the speed of the drive.

You don't seem to understand what I am saying.

Memory is memory and disk caching is disk caching. A 32Bit OS can only make use of 4GB memory before making use of disk caching.
 
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A 32-bit OS (note I did not say "windows") using PAE can directly address up to 64GB of RAM, regardless of any one program being able to use only 4GB of it at a time... in protected mode, each program can use up to 4GB (assuming the motherboard's capable of holding 4GB x the number of programs) and never have to swap anything to disk.
 
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Ian

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I think this thread has run its course, as it's quite a bit different to the original post now ;)
 
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