[BALU] 64 bit systems

Thomas Stover thomas at wsinnovations.com
Fri Jun 8 11:10:00 CDT 2007

2 to the 48th power divided by 8 = max number of RAM bytes. There may be 
other limitations added by the os though. Windows limits that number a 
great deal.

Mr. Panzer wrote:

> ok so how much ram we talking about?
>> From: Thomas Stover <thomas at wsinnovations.com>
>> The physical address space is 48 bits, so that limits the amount of 
>> real ram in the system. However from a process's point of view the 
>> "virtual" address space is 64 bits, and that could still be utilized 
>> with file mapping and /or  NUMA  machines.
>> jim wrote:
>>> Is not the address space only 48 bits, 256 terabytes
>>> <http://en.wikipedia.org/wiki/Tebibyte>.    (I am looking foward to
>>> buying 1 terabyte[1000 gigabytes] surplus memory). and the actual 
>>> Ram only 40 bit addressing or just 1 terabyte of RA.
>>> But the registers and data width are 64 bits are they not.
>>> I think the 40 and 48 restrictions are only for memory ops.

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