Hello,

I have read a number of threads on various forums regarding the fact
that XP/Vista 64 and other 64-bit OS's can, in some cases and with some
tinkering, access more RAM than the 32-bit versions. There must be a
million sites out there explaining why the 32-bit versions cannot access
more than around 2.5 or 3 gb. I am yet to find a site, though, that
demonstrates objective performance improvements in the 64-bit versions
as a result of adding additional RAM - more than, say, 3 or 4 gb. Has
anyone done any objective comparisons or observed any measurable
improvements with the 64-bit operating systems by using addtional RAM
above what can be seen in 32 bit versions? I am using 2 gb of RAM and I
know I may get a slight improvement with an additional 1gb in 32-bit
versions, but what about going up to,say, 8 gb or more in 64-bit
versions?


--
archp2008

"Rick Rogers" schreef in bericht
...
Hi,

In brief: The only time extra ram available in a 64-bit OS will be useful
is when programs are written to take advantage of it. By far, the vast
majority of software currently available to the consumer market is still
32-bit, and cannot utilize the extra memory. The problem arises in the
memory addresses, as 32-bit programs cannot use the upper memory
addresses, so when they are loaded they must be placed in the lower range,
bumping out anything that currently exists there.

--
Best of Luck,

Rick Rogers, aka "Nutcase" - Microsoft MVP

With 64 bit Windows each 32 bit program can use up to 4GB address space.
For compatibility reasons programs must be marked to use more then 2GB (the
same is true on 32 bit windows).

I don't know wat you mean by bumping out. Addresses are local to a process
and you can have multiple 32 bit programs running at the same time, that use
4GB of memory each (and without swapping if you have enough RAM on your
system).

Windows also uses RAM for caching files. So even if the active programs
don't use more then 3Gb, performance can be increased by using the extra
memory for caching.

Greetings,
Hans.

Thanks for the replies. I was beginning to assume what Rick had said.
I would like to know if anyone has actually measured the benefits of
increased RAM when multitasking or increasing cache size in 64-bit
compared to 32-bit. I'm wondering, for example, how much faster tasks
basic tasks would be with background video encoding in 64-bit Vista or
XP compared to 2 or 3 gb in 32-bit versions. I'm using a Pentium D 3.4
GHz processor on an Asus P5B-VM motherboard. Right now I'm lucky to be
able to do anything else while video encoding and burning without
risking errors or crashes. My 64-bit systems seem to be working better
at the moment, but I suspect it's only because there is more disk space
on the latter partitions. I haven't tried additional RAM above 3gb.


--
archp2008