PC 4GB RAM limit

"David Maynard" wrote in message
...
It can't because a remap would place it outside of 4 gig and it can only
address 4 gig.

Yes, I know it can't. But a better designed board could. That's the point.

Manufacturers like Asus and MSI are now doing this with AMD boards in the
same price range.

Tim

http://support.microsoft.com/default...b;en-us;888855


"David Maynard" wrote in message
...
Tim Anderson wrote:
"David Maynard" wrote in message
...

Tim Anderson wrote:

"David Maynard" wrote in message
...


It is not advertised as "more than 4 gig". It is advertised as 4 gig;
but in fact only offers 3 usable GB.

And it *does* have 4 Gig addressing capability.


I think I have a good understanding of this issue now. There is an
inherent problem with this top 1GB of address space. It is possible for
boards to overcome it by remapping. This board doesn't though.
Personally, I think it should;

It can't because a remap would place it outside of 4 gig and it can only
address 4 gig.

Remember, we're talking *physical* address space and to physically remap
memory above 4 gig the board would need at least one more address line,
which would mean it could address 8 gig. But it isn't an 8 gig
motherboard.

(I'm not sure what's actually 'missing' on the board because the chipset
specs suggest the chipset itself could address 8 gig but 'something' is
apparently missing. The point being adding that 'feature' may not be as
trivial as it seems.)

and I think Intel should make the problem clearer;

I agree with that. The only explanations I can think of off the top of my
head are 1. they didn't really expect folks putting 4 gig in it would be
all that common and/or 2. their primary market is system
builders/manufacturers who are expected to read the detailed
documentation.

but it's no big deal. I raised it here because I wanted to understand it
better.


When you get to the technical documentation
(http://www.intel.com/design/motherbd/bl/index.htm)
EM64T 'support' becomes more obvious, but then a system builder should
also read all of it.


It either supports it or it doesn't,

That depends on what "it" is.

If "it" is being able to run an EM64T processor in 64 bit mode then the
board supports "it."

If "it" is having an address space larger than 4 gig then the board does
not support "it."

Now, the second 'it', being what? a terabyte?, is not going to be 'fully'
implemented no matter what so you *know* there has to be a limit
*somewhere* with *any* board which 'supports' EM64T. It happens to be 4
gig on this one.


no matter what the marketers say or don't say.

Seems to me you might want to consider this example a warning that you
need to pay more attention to what they say

I'd have thought a design engineer would understand that :-)

A design engineer understands what he's told to design and, when designing
a motherboard in the 2003-2004 time period, putting in 'support' for
things that don't yet exist isn't necessarily a part of it. And if the
spec says "design a P4 motherboard with 4 gig address space" then that's
what he'll design, if he's smart.

And, btw, I'm not being frivolous about that. One of the biggest problems
design engineers have is folks coming in after it's all said and done
complaining "how come you didn't include X?"

Because it WASn't IN the SPEC!

The second biggest problem is the poor engineer who thought he'd be clever
and include some neat things having to explain why he's wasting resources
on something that WASn't IN the SPEC.

And I tell ya, it's usually a heck of a lot easier to answer number 1 than
it is to explain number 2.


Tim

"Phil Weldon" wrote in message
ink.net...
http://support.microsoft.com/default...b;en-us;888855

Not relevant here Phil, this is not an OS issue (and I'm using 64-bit OS in
any case).

Tim

Phil Weldon wrote:
http://support.microsoft.com/default...b;en-us;888855

I made the same mistake the first time around but he's using XP/64 and 64
bit Linux.

And, according to his description, the motherboard BIOS post screen reports
the after mentioned 'missing' memory is "consumed by system" long before
the matter of which OS later boots enters into the equation.



"David Maynard" wrote in message
...

Tim Anderson wrote:

"David Maynard" wrote in message
...


Tim Anderson wrote:


"David Maynard" wrote in message
...


It is not advertised as "more than 4 gig". It is advertised as 4 gig;
but in fact only offers 3 usable GB.

And it *does* have 4 Gig addressing capability.


I think I have a good understanding of this issue now. There is an
inherent problem with this top 1GB of address space. It is possible for
boards to overcome it by remapping. This board doesn't though.
Personally, I think it should;

It can't because a remap would place it outside of 4 gig and it can only
address 4 gig.

Remember, we're talking *physical* address space and to physically remap
memory above 4 gig the board would need at least one more address line,
which would mean it could address 8 gig. But it isn't an 8 gig
motherboard.

(I'm not sure what's actually 'missing' on the board because the chipset
specs suggest the chipset itself could address 8 gig but 'something' is
apparently missing. The point being adding that 'feature' may not be as
trivial as it seems.)


and I think Intel should make the problem clearer;

I agree with that. The only explanations I can think of off the top of my
head are 1. they didn't really expect folks putting 4 gig in it would be
all that common and/or 2. their primary market is system
builders/manufacturers who are expected to read the detailed
documentation.


but it's no big deal. I raised it here because I wanted to understand it
better.



When you get to the technical documentation
(http://www.intel.com/design/motherbd/bl/index.htm)
EM64T 'support' becomes more obvious, but then a system builder should
also read all of it.


It either supports it or it doesn't,

That depends on what "it" is.

If "it" is being able to run an EM64T processor in 64 bit mode then the
board supports "it."

If "it" is having an address space larger than 4 gig then the board does
not support "it."

Now, the second 'it', being what? a terabyte?, is not going to be 'fully'
implemented no matter what so you *know* there has to be a limit
*somewhere* with *any* board which 'supports' EM64T. It happens to be 4
gig on this one.



no matter what the marketers say or don't say.

Seems to me you might want to consider this example a warning that you
need to pay more attention to what they say


I'd have thought a design engineer would understand that :-)

A design engineer understands what he's told to design and, when designing
a motherboard in the 2003-2004 time period, putting in 'support' for
things that don't yet exist isn't necessarily a part of it. And if the
spec says "design a P4 motherboard with 4 gig address space" then that's
what he'll design, if he's smart.

And, btw, I'm not being frivolous about that. One of the biggest problems
design engineers have is folks coming in after it's all said and done
complaining "how come you didn't include X?"

Because it WASn't IN the SPEC!

The second biggest problem is the poor engineer who thought he'd be clever
and include some neat things having to explain why he's wasting resources
on something that WASn't IN the SPEC.

And I tell ya, it's usually a heck of a lot easier to answer number 1 than
it is to explain number 2.



Tim

I was more interested in th 'some chipsets' phrase. The rest I don't
understand at all.

"David Maynard" wrote in message
...
Phil Weldon wrote:
http://support.microsoft.com/default...b;en-us;888855

I made the same mistake the first time around but he's using XP/64 and 64
bit Linux.

And, according to his description, the motherboard BIOS post screen
reports the after mentioned 'missing' memory is "consumed by system" long
before the matter of which OS later boots enters into the equation.

Phil Weldon, , the narrow-minded, windward haddock,
and flax dresser, retched:

I was more interested in th 'some chipsets' phrase. The rest I don't
understand at all.

Some \Some\ (s[u^]m), a. [OE. som, sum, AS. sum; akin to OS.,
OFries., & OHG. sum, OD. som, D. sommig, Icel. sumr, Dan.
somme (pl.), Sw. somlige (pl.), Goth. sums, and E. same.
[root]191. See Same, a., and cf. -some.]
1. Consisting of a greater or less portion or sum; composed
of a quantity or number which is not stated; -- used to
express an indefinite quantity or number; as, some wine;
some water; some persons. Used also pronominally; as, I
have some.

chip set

A collection of integrated circuits that are
designed to be used together for some specific purpose.
E.g. control circuitry in an IBM PC.

Phil Weldon wrote:

I was more interested in th 'some chipsets' phrase.

I'm not sure what they mean either unless it has to do with chipsets that
*do* remap himem so PAE would work, vs those that just tell you how much
you've lost to the system.


The rest I don't
understand at all.

You don't understand the PAE part?


"David Maynard" wrote in message
...

Phil Weldon wrote:

http://support.microsoft.com/default...b;en-us;888855

I made the same mistake the first time around but he's using XP/64 and 64
bit Linux.

And, according to his description, the motherboard BIOS post screen
reports the after mentioned 'missing' memory is "consumed by system" long
before the matter of which OS later boots enters into the equation.

Haven't bothered to, as 4 GBytes is far in my future.

"David Maynard" wrote in message
...
Phil Weldon wrote:

I was more interested in th 'some chipsets' phrase.

I'm not sure what they mean either unless it has to do with chipsets that
*do* remap himem so PAE would work, vs those that just tell you how much
you've lost to the system.


The rest I don't understand at all.

You don't understand the PAE part?

Phil Weldon wrote:
Haven't bothered to, as 4 GBytes is far in my future.

Yeah. 4 gig is a 'future' thing for me too. But when you get to the 4 gig
stage go 64 bit and what PAE is won't matter anyway,


"David Maynard" wrote in message
...

Phil Weldon wrote:


I was more interested in th 'some chipsets' phrase.

I'm not sure what they mean either unless it has to do with chipsets that
*do* remap himem so PAE would work, vs those that just tell you how much
you've lost to the system.



The rest I don't understand at all.

You don't understand the PAE part?

On Wed, 18 May 2005 11:07:04 -0500, David Maynard
wrote:

Haven't bothered to, as 4 GBytes is far in my future.

Judging from the pace at which Windows bloats, it may be sooner than
you think.

Yeah. 4 gig is a 'future' thing for me too. But when you get to the 4 gig
stage go 64 bit and what PAE is won't matter anyway,


4 GB of RAM is obscene. I can remember when a 20 MB HD was considered
large.

I suppose you could set up 3 GB RAM disk. I bet that sucker would
scream.


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Million Mom March For Gun Confiscation
http://home.houston.rr.com/rkba/mmm.html

A liberal is a person who is so open minded
that their brains have fallen out.