4 GB with 32-bit OS

If i'm not mistaken 32-bit OS is only able to use 3 GB of RAM and no more. That's one of the limitations of a 32-bit OS. However, if you ever decide to go 64 you'll be set.
 
it uses something like 3.35 of the 4gb. i have 32bit vista with 4x1gb sticks.
 
That article is mistaken. Microsoft doesn't want to support more than 4GB in 32bit XP/Vista. Not even with PAE enabled.
 
CrypticHorde said:
If i'm not mistaken 32-bit OS is only able to use 3 GB of RAM and no more. That's one of the limitations of a 32-bit OS. However, if you ever decide to go 64 you'll be set.
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bufodr_T said:
it uses something like 3.35 of the 4gb. i have 32bit vista with 4x1gb sticks.
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The truth is that the amount of usable RAM on a 32-bit system varies from system to system. If the address space of a machine is 2^32 bytes (4GB)and someone installs 4GB of RAM and a 256MB video card, the usable memory will be ~3.75GB, due to the effects of memory-mapped I/O. If the same person replaced the 256MB video card with a 512MB card, then the usable memory drops another 256MB for the same reason. Note, though, that this example didn't take into account other memory-mapped hardware.

How about a system with 3GB of memory installed and a 512MB video card? If 512MB are consequently deducted from the 4GB address space, then ~3.5GB remains and all 3GB of RAM are usable.

What of a system with a 1GB video card? Taking 1GB from the 4GB address space yields a remaining 3GB of which the 3GB of RAM should be able to occupy, and thus, be usable. Again, not taking into account other memory-mapped hardware or reservations in the address space.
pallesen said:
That article is mistaken. Microsoft doesn't want to support more than 4GB in 32bit XP/Vista. Not even with PAE enabled.
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The reason really comes down to driver support within a 36-bit address space.
 
damn dude, that's some good info!

I'm tempted by the $5 deal for 2x1GB DDR2 for my upgrade to Core 2, since I'm still using XP 32 bit for now. But i guess 3 GB is still better than 2 GB.
 
Thanks for the information - much appreciated!!! Thanks for clearing that up. A usual, can't trust many postings.....

Varmint said:
damn dude, that's some good info!

I'm tempted by the $5 deal for 2x1GB DDR2 for my upgrade to Core 2, since I'm still using XP 32 bit for now. But i guess 3 GB is still better than 2 GB.
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Yeah, I am with you. It is such a cheap and easy update, it is worth it even if it can't utilize all the RAM.

I will evenually go to 64-bits, but until I get off my lazy ass, another GB should help out nicely!
 
Varmint said:
damn dude, that's some good info!

I'm tempted by the $5 deal for 2x1GB DDR2 for my upgrade to Core 2, since I'm still using XP 32 bit for now. But i guess 3 GB is still better than 2 GB.
Click to expand...


What??? $5 for 2GB?
 
Is there an utility or some way of checking how your address space is being allocated? That is, how much address space is allocated to each memory-mapped component.
 
rflcptr said:
The truth is that the amount of usable RAM on a 32-bit system varies from system to system. If the address space of a machine is 2^32 bytes (4GB)and someone installs 4GB of RAM and a 256MB video card, the usable memory will be ~3.75GB, due to the effects of memory-mapped I/O. If the same person replaced the 256MB video card with a 512MB card, then the usable memory drops another 256MB for the same reason. Note, though, that this example didn't take into account other memory-mapped hardware.

How about a system with 3GB of memory installed and a 512MB video card? If 512MB are consequently deducted from the 4GB address space, then ~3.5GB remains and all 3GB of RAM are usable.

What of a system with a 1GB video card? Taking 1GB from the 4GB address space yields a remaining 3GB of which the 3GB of RAM should be able to occupy, and thus, be usable. Again, not taking into account other memory-mapped hardware or reservations in the address space.

The reason really comes down to driver support within a 36-bit address space.
Click to expand...

Don't be silly.... let's say that you have 1GB of system RAM and a GTX-280 that has 1GB of memory. So, does that mean that your address space is now at zero? Oh please... cut me the BS!
 
Bo_Fox said:
Don't be silly.... let's say that you have 1GB of system RAM and a GTX-280 that has 1GB of memory. So, does that mean that your address space is now at zero? Oh please... cut me the BS!
Click to expand...

No, you have to subtract your video ram from 4 GB, which is the theoretical max for a 32 bit CPU (2 bit ^32 = 4 Gigabyte). So you'd have 3 GB addressable and 1 GB ram. No problemo. :)

pallesen said:
#12 device manager or msinfo32 can show you
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Where in msinfo32 does it show this?
 
i will say you couldnt of searched too hard cause there are tons of the 32bit - 4G threads.

but either way some interestnig info in here.
 
There's a lot of FUD on this subject outthere. The long and short of it is, 32bit consumer Microsoft operating systems use a system wide 32 bit logical adress map for all "speedy" memory operations. It can't really be described any other way since it's pretty arbitrary by design; since win2k, microsofts 32bit enterprise server operating systems have used a larger logical adress maps.

This is because all hardware since the pentium pro has been using a 36bit memory bus, so there's no actual hardware limitation to the adress space. Since modern MS operating systems use virtual memory, that is, logical memory adresses, it remaps every memory adress used by programs completely dynamically anyway - this is what allows it to write pages to disc. So there's nothing within the hardware that prohibits a 32 bit operating system from simply mapping a lot of 32 bit programs with lots of logical adress spaces within a full 64 gigabyte(36bit) memory pool;

Only thing in the way is drivers, many of which have presumably been written under the presumption that a flat system-wide 32bit memory map exists. For that reason, Microsoft has more or less given up on 32bit drivers.

But yeah, this is why you can use any additional memory beyond the first 4gb or so for a ramdrive perfectly fine - but you can't use it directly within the operating system. Of course, microsoft would rather switch away from 32bit operating systems altogether because it creates many complexities and it incurs steep performance penalties and...quite frankly....I think they'd like to start over.

But if they really wanted, they could easily support much more ram on 32bits. They could actually breathe life into it for another 5 years at least, if they wanted to, at least as far as I can figure.
 
Just get 8GB of RAM. It's about $100 right now for DDR2. Then you can just go 64 bit and not have to worry about this anymore. ;)
 
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