Housemate's laptop with Vista 32bit and 4Gb ram

Tea_Bag

when i click on "my computer > properties", it displays that is is a 32bit operating system and it has 4gb of ram. shouldnt it say 3.2gb? should i do a reinstall to 64bit vista or is it somehow reading and using the 4gb?

cpu-dude

Tea_Bag wrote: »

when i click on "my computer > properties", it displays that is is a 32bit operating system and it has 4gb of ram. shouldnt it say 3.2gb? should i do a reinstall to 64bit vista or is it somehow reading and using the 4gb?

Microsoft realesed an update a while back that shows how much RAM a 32-bit system has but it still only utilises 3.2GB of it.

Tea_Bag

cpu-dude wrote: »

Microsoft realesed an update a while back that shows how much RAM a 32-bit system has but it still only utilises 3.2GB of it.

excelent thanks man. format time. i dont use vista or 4gb of ram so i had no idea.

actually it would be really ****ty if compaq hp didnt supply a 64bit vista on the recovery partition. and im willing to bet they didnt.

kaizersoze

Tea_Bag wrote: »

actually it would be really ****ty if compaq hp didnt supply a 64bit vista on the recovery partition. and im willing to bet they didnt.

Prepare to be disappointed. They mightened even provide 64bit drivers on their website. I'd be checking that first.

Btw, you won't notice any difference going to 64bit. It won't unleash ant 'hidden' power in the machine.

Tea_Bag

thats really annoying.

why would they supply 4gb ram when their own product cant and wont support it??

cpu-dude

Tea_Bag wrote: »

thats really annoying.

why would they supply 4gb ram when their own product cant and wont support it??

It's a Windows limit, not HP's. It's simply how all 32-bit operating systems work and the reason the offer 4GB because it's:

1 - It's cheaper for them to buy 2GB RAM Modules in bulk (not 2GB and 1GB).
2 - They can legally advertise it has 4GB of RAM (not 3GB).
3 - Windows can use the max RAM available to it's architecture (usually 3.3GB, better since there's no 1.3GB RAM chips).
4 - Other parts of the computer utilise the RAM as well so it's spread out (see ** below).

If you are running 32-bit Windows, you must live with it. You will not ever see all 4GB of RAM you've paid for.

If you are running 64-bit Windows, you may have to live with it. Depending on your motherboard's chipset, your system may support memory remapping. If so, you will be able to use all 4GB of RAM.

Detailed:
Due to an architectural decision made long ago, if you have 4GB of physical RAM installed, Windows is only able to report a portion of the physical 4GB of RAM (ranges from ~2.75GB to 3.5GB depending on the devices installed, motherboard's chipset & BIOS).

This behavior is due to "memory mapped IO reservations". Those reservations overlay the physical address space and mask out those physical addresses so that they cannot be used for working memory. This is independent of the OS running on the machine.

** Significant chunks of address space below 4GB (the highest address accessible via 32-bit) get reserved for use by system hardware:

• BIOS – including ACPI and legacy video support

• PCI bus including bridges etc.

• PCI Express support will reserve at least 256MB, up to 768MB depending on graphics card installed memory

What this means is a typical system may see between ~256MB and 1GB of address space below 4GB reserved for hardware use that the OS cannot access. Intel chipset specs are pretty good at explaining what address ranges gets reserved by default and in some cases call out that 1.5GB is always reserved and thus inaccessible to Windows.

Continue Reading...

Another reason why vendors install 4GB of RAM on 32-bit machines is because to install 3GB would cause the memory controller to fall back to single channel mode, therefore reducing performance. Even if the OS can't use all of the RAM it will still have the benefit of increased bandwidth from dual channel operation.

Capt'n Midnight

Tea_Bag wrote: »

thats really annoying.

why would they supply 4gb ram when their own product cant and wont support it??

RAM prices are low , in bulk the price difference between 3GB and 4GB isn't all that much
3.2GB is better than 3GB
as above with RAM timing
some of the RAM may be used by the motherboard esp. if you have a shared memory video card


Back in the day you would get a PC with 1MB of RAM and you could only use 640K of it without serious configuring of drivers, crazy stuff like accessing bits of memory each side of the video cards / scsi cards and network cards and then using the keyboard controller to access 64K of memory remapped past the 1MB boundary,

nowadays with 64bit available no one is going to kill themselves to fix a problem that affects only lower end PC's at their ram limit