How much ram can W7 really use?

[Jeff]

I have an Intel Core Duo CPU (P7450 @ 2.13GHz) computer with 6 GB
installed RAM running Windows 7 64 bit Home Premium. But I've been told
that my apps can only use the first 4 GB of RAM.

Is that true? If so what use are the additional 2 GB RAM?

Thanks, Jeff

 

[Yousuf Khan]

I have an Intel Core Duo CPU (P7450 @ 2.13GHz) computer with 6 GB
installed RAM running Windows 7 64 bit Home Premium. But I've been told
that my apps can only use the first 4 GB of RAM.

Is that true? If so what use are the additional 2 GB RAM?

If your apps are 32-bit apps, running under the 64-bit operating system,
then yes, they can only use 4GB in total. If they are full 64-bit apps,
then they can use the entire allotment of RAM that Windows 7 64-bit has
available to it.

However, on a related note, not all Windows 7 64-bits are built alike.

Memory Limits for Windows Releases (Windows)
http://msdn.microsoft.com/en-us/library/aa366778(VS.85).aspx#physical_memory_limits_windows_7

Here are the upper RAM limits for the different editions of Windows 7:

Starter (32-bit only): 4GB
Home Basic: 8GB
Home Premium: 16GB
Professional: 192GB
Enterprise: 192GB
Ultimate: 192GB

Yousuf Khan

 

[Jeff]

If your apps are 32-bit apps, running under the 64-bit operating system,
then yes, they can only use 4GB in total. If they are full 64-bit apps,
then they can use the entire allotment of RAM that Windows 7 64-bit has
available to it.

However, on a related note, not all Windows 7 64-bits are built alike.

Memory Limits for Windows Releases (Windows)
http://msdn.microsoft.com/en-us/library/aa366778(VS.85).aspx#physical_memory_limits_windows_7


Here are the upper RAM limits for the different editions of Windows 7:

Starter (32-bit only): 4GB
Home Basic: 8GB
Home Premium: 16GB
Professional: 192GB
Enterprise: 192GB
Ultimate: 192GB

Yousuf Khan

Thank you. That is very useful.

I know there are some 64 bit apps, but since most apps that the average
user uses today are 32 bit, it sounds like anything beyond 4GB is really
wasted ram.

Jeff

 

[Paul]

Thank you. That is very useful.

I know there are some 64 bit apps, but since most apps that the average
user uses today are 32 bit, it sounds like anything beyond 4GB is really
wasted ram.

Jeff

If you run four 2GB programs, your 8GB is now used up.

If you use Virtual Machines regularly, the RAM gets used up pretty
fast. I've had as many as three of them running at the same time,
and ran out of system ram to do virtually anything else.

Paul

 

[Jeff]

If you run four 2GB programs, your 8GB is now used up.

If you use Virtual Machines regularly, the RAM gets used up pretty
fast. I've had as many as three of them running at the same time,
and ran out of system ram to do virtually anything else.

Paul

Aha! I misunderstood. So, because a 32 bit app can only use 4GB another
running 32 bit app can use a "different" ram because W7 makes it
available to it. That's cool.

Jeff

 

[Ivan I. Deer]

One ram is usually able to take care of the needs of about 20 ewes.

 

[Tim Slattery]

I have an Intel Core Duo CPU (P7450 @ 2.13GHz) computer with 6 GB
installed RAM running Windows 7 64 bit Home Premium. But I've been told
that my apps can only use the first 4 GB of RAM.

The amount of physical RAM that 64bit Win7 can use is extremely high.
AFAIK, the limitation these days is always in the hardware, not the
Win7 software. So all of your 6GB is seen and used by 64bit Win7.

32-bit programs are all assigned a 4GB virtual address space when they
run. (64-bit programs are assigned a much larger VM space). The OS
tries to keep as much of all these VM spaces in physical RAM as it
can. It's an *extremely* complex system involving swapping pages of
storage between RAM and the swap file on your hard drive. The more
physical RAM in your machine, the more of the VMs can reside there,
and the less time your machine will spend swapping pages.

So *all* of your physical RAM will be used, and having more of it will
speed up your 32-bit programs, especially if you run many of them
simultaneously or if you run RAM-hungry apps.

 

[Zaphod Beeblebrox]

The amount of physical RAM that 64bit Win7 can use is extremely
high.
AFAIK, the limitation these days is always in the hardware, not the
Win7 software.

Except when the limitation *is* Win7 - you might take a look at Yousuf
Khan's reply elsethread which lists the arbitrarily limits MS has
imposed in various flavors of Win7. I agree, in this case Win7 isn't
limiting access to the 6GB memory since the OP is using Win7 Home
Premium, but all the same...

 

[Tim Slattery]

Except when the limitation *is* Win7 - you might take a look at Yousuf
Khan's reply elsethread which lists the arbitrarily limits MS has
imposed in various flavors of Win7. I agree, in this case Win7 isn't
limiting access to the 6GB memory since the OP is using Win7 Home
Premium, but all the same...

Point taken. Win7 64-bit limits:

Starter: (not available in 64-bit version)
Home Basic: 8GB
Home Premium: 16GB
Professional, Enterprise, Ultimate: 192GB

Entirely arbitrary as you say, Zaphod.


(Source:
http://msdn.microsoft.com/en-us/library/aa366778(v=vs.85).aspx#physical_memory_limits_windows_7
)

 

[charlie]

Point taken. Win7 64-bit limits:

Starter: (not available in 64-bit version)
Home Basic: 8GB
Home Premium: 16GB
Professional, Enterprise, Ultimate: 192GB

Entirely arbitrary as you say, Zaphod.


(Source:
http://msdn.microsoft.com/en-us/library/aa366778(v=vs.85).aspx#physical_memory_limits_windows_7
)

And, possibly, with some effort, the RAM limits (License restriction)
can be gotten around. The information is generally correct for Vista and
Win 7.
http://www.geoffchappell.com/viewer.htm?doc=notes/windows/license/memory.htm

 

[Gene E. Bloch]

elsethread

Cute...once I figured it out

 

[Zaphod Beeblebrox]

Cute...once I figured it out

I stumbled across it once and thought it worked, so adopted it. Doubt
you'll ever see it in Webster's but all the same... ;-)

 

[Gene E. Bloch]

I stumbled across it once and thought it worked, so adopted it. Doubt
you'll ever see it in Webster's but all the same... ;-)

Well, heck, what does Webster know?