vic said:
It is an XFX Mother board 680i LT. It has a 2.4 gig intel quad chip. It
has 2 EVGA 8600 Gt video cards with 512 meg of DDR3 in SLI. I have 6 gig of
ram 6400 dual channel. I ahve 2- 500 gig hard drives SATA. (by the way my
motherboard says it cant find any mass storage when starting It makes me hit
F1 every time then runs normally.) Home built computer. I wanted something
to run Flight Sim with all graphics. Think this will do it.? So if I get
XP64 bit it will see all 6 meg? What about VISTA.
A 64 bit OS will be able to make use of more memory. There are some
examples of supported limits in this article. WinXP x64 can handle
up to 32GB.
http://dlsvr01.asus.com/pub/ASUS/mb/4GB_Rev1.pdf
On some of the Intel chipset boards, there is a "memory remap" option
in the BIOS, and the BIOS instructions say to only enable it when using
a 64 bit OS. The 680i, on the other hand, doesn't appear to offer
a setting to change anything there. So I presume, somehow, it does the
right thing, when more than 4GB is present.
Another thing to remember, is the application itself has limitations. If
the application is 32 bit only, and the developers didn't do anything
special, the program might be limited to 2GB internally. With the appropriate
compiler flag, they can go to 3GB. If the program was compiled for use
in a 64 bit OS (program was also 64 bit), the limit goes up, but
still might not be as high as you'd think. And that is the hard part
of constructing systems with massive amounts of memory - there is a
lot of research to do, to determine whether it is doing any good or not.
There is at least one guy in the groups, who seems to have a good handle
on that stuff (Roger Hamlett). I know that issues exist, but have
no first hand knowledge of the >4GB stuff.
With a 64 bit OS, I don't expect a problem shoehorning 6GB of RAM
and the video cards, below 8GB. The chipset sometimes causes an issue,
by being capped at 8GB of address space. I would guess that there
is sufficient room, so that you'll get all 6GB. If you installed
8GB total, then you wouldn't be able to address all 8GB. This
has to do with the addressing limits of a chipset. Some chipsets
handle more than 8GB, in which case, installing 8GB plus a couple
video cards, wouldn't be a problem. That kind of addressing capability
is more likely to be present on some kind of server board.
Paul
Paul said:
vic said:
I had two 1 meg chips and had 2 meg ram. I installed two 2 meg chips in
addition. I put the two 2 meg chips in slots 0 and 1. I put the two 1
meg chips in 2 and 3. When I checked I had 2.5 meg of ram instead of 6.
I checked each chip in slot 0 and they all work I tried different slots
and still had 2.5 meg. I tried the 2 2 meg chips alone and still only
had 2.5. I checked my book and my mother board supports 8 meg. Any
ideas. I believe it is a Windows problem
A 64 bit OS would see the extra memory.
Also, check the user manual for the motherboard. This is an example
of the setting you use, to make all the memory usable in a 64 bit OS.
"Memory Remapping Feature [Enabled]
Allows you to enable or disable the remapping of the overlapped PCI
memory
above the total physical memory. Enable this option only when you
install
64-bit operating system."
Based on the report that you can see 2.5GB, my guess would be
you have two video cards running SLI or Crossfire. That low of a
reported amount of memory, typically happens on a dual video card
system.
If you still have questions, please identify either the motherboard make
and model, or the computer make and model. Providing some background
info, makes it easier to answer questions in a specific way.
HTH,
Paul
