Andrew McNab

Workload isn't the issue. Especially when the addresses of the 2nd two gigs
is far out of the range of startup memory requirements. The OS uses the BIOS
to determine the amount of ram, PCI devices and drives etc. Considering that
it hasn't had a problem with any other hardware devices, it seems to be a
very specific issue. Especially since the methodology of addressing memory is
static for any OS running on the machine. Fetching and setting is managed by
the mother board.

Hardware performance failure due to stress is generally a result of
overclocking heat or external heat and in both cases, I take carefull
measures to ensure I don't overclock or expose the chassis to heat. Under
these conditions, RAM only fails if it is physically damaged and a read
instruction occurs in an area that a DDR transistor circuit has failed.

Rather than pinning the blame on something in particular, I'd be more
interested to find out the discrepency in total memory installed. Allthough I
use .Net framework and Server 2003 religiously, i'm poking MS in the belly on
this one. Handballing it off to the mother board or precisely matched SIMS
isn't a reasonable conclusion.

"Richard Urban" wrote:

> The fact that the bios recognizes the RAM means nothing to Windows. Vista
> works the RAM much more intensely than any previous version of Windows ever
> did. If you don't have "precisely" ***matched*** RAM - you may well have
> problems.
>
> I previously had 2-500 meg sticks of matched RAM. I wanted to move to 2 gig
> of RAM. I purchased 2 NEW 1 gig sticks of RAM (at the same time to be
> certain they even came from the same date/batch/lot). I could have just
> purchased a single 1 gig stick and I would have had 2 gig. The RAM would NOT
> have been matched - even though it was all identified in the bios.
>
> --
>
>
> Regards,
>
> Richard Urban
> Microsoft MVP Windows Shell/User
> (For email, remove the obvious from my address)
>
>
>
> "Andrew McNab" <AndrewMcNab@discussions.microsoft.com> wrote in message
> news:AB2FB012-2807-46C5-B9B3-5D61141976D0@microsoft.com...
> > In my original post, I made it clear that the BIOS properly recognised the
> > memory. All 4 SIMS are 667MHz and both memory channels have matched SIMS.
> > The
> > conditions can't be any more ideal.
> >
> > The mother board supports 800/667 etc with up to 8GB addressed at 64-bits.
> > I
> > also stated that i'm using 3 SIMS for now. The original pair and a single
> > sim
> > in the second memory channel making it 3GB. I've tested both SIMS and
> > they're
> > fine.
> >
> > The obvious question is, why is there a discrepency between the BIOS and
> > Windows in terms of the amount of memory that is installed in the machine?
> > BIOS reporting 4072 and Windows reporting 3582 with all four SIMS and both
> > reporting 3000 with 3 SIMS.
> >
> > Having been a developer on every version of Windows since Windows for
> > Workgroups 3.11, i'm more inclined to believe it's a teething problem.
> >
> > "Richard Urban" wrote:
> >
> >> If your system is crashing when you install the extra RAM you must look
> >> at
> >> the manual for your M/B to determine what the RAM specifics are. All 1
> >> gig
> >> sticks RAM are not the same. Some are single sided. Some are double
> >> sided.
> >> There are timing frequencies. The list goes on.
> >>
> >> --
> >>
> >>
> >> Regards,
> >>
> >> Richard Urban
> >> Microsoft MVP Windows Shell/User
> >> (For email, remove the obvious from my address)
> >>
> >>
> >>
> >> "Andrew McNab" <AndrewMcNab@discussions.microsoft.com> wrote in message
> >> news:C28EC6C8-EAE6-4087-8C8D-F8354E669D18@microsoft.com...
> >> > I've been running Vista Ultimate on 2GB of RAM fine but decided to
> >> > upgrade
> >> > to
> >> > 4GB because the prefetch cache got up to 1.4GB. My BIOS reports 4075MB
> >> > of
> >> > installed and useable RAM. Supports up to 8GB.
> >> >
> >> > Windows Vista only reports 3528MB RAM and results in a Blue Screen
> >> > crash
> >> > when logging in or shortly afterwards. I tested the 2 new SIMS by
> >> > themselves
> >> > and tried combinations of the original 2 SIMS and either of the 2 new
> >> > SIMS
> >> > to
> >> > make 3GB. Windows reports 3GB of RAM and runs fine.
> >> >
> >> > I was wondering if there was an issue with a certain amount of memory
> >> > the
> >> > OS
> >> > can work with at this point. I'm running Vista Ultimate with the latest
> >> > OS
> >> > updates.
> >>
> >>
>
>