32 or 64bit?

[Oops_my_bad]

Even though it says it can support upto 64gig of RAM, can the enterprise version of 2008 (x86) actually see/use this amount? I have a quad core machine, with 4gig per core which will be used heavily for citrix. Will the 32bit version make good use of all 4 cores and RAM, or should I install the 64 bit version? Seeing as though Microsoft are forcing us to go 64bit

[Michael]

According to this Enterprise and Datacenter support 64GB. I think the issue is more about the applications you're hosting and how many users is it hosting for?

[Oops_my_bad]

Thanks, the only stumbing block preventing me going full 64 bit is one or 2 apps the ICT department use that are 16 bit

[powdarrmonkey]

Thanks, the only stumbing block preventing me going full 64 bit is one or 2 apps the ICT department use that are 16 bit

Yeeeesh. This is a good time to pretend to your department head that there is no such thing as a 32 bit OS any more

[Michael]

Well they'd be nothing stopping you running Server 2008 Standard with upto 4GB of memory on server 1 and Server 2008 Enterprise with 16Gb of memory on server 2 in the same network.

[Oops_my_bad]

Well they'd be nothing stopping you running Server 2008 Standard with upto 4GB of memory on server 1 and Server 2008 Enterprise with 16Gb of memory on server 2 in the same network.

Well yes but I like everything uniform and besides, all our media/licences is for enterprise so why the hell not

[somabc]

Even though it says it can support upto 64gig of RAM, can the enterprise version of 2008 (x86) actually see/use this amount? I have a quad core machine, with 4gig per core which will be used heavily for citrix. Will the 32bit version make good use of all 4 cores and RAM, or should I install the 64 bit version? Seeing as though Microsoft are forcing us to go 64bit

The 32bit version can use (nearly) 4GB total. You have 4x4GB= 16GB so you should definitely use 64 bit or you will waste 12GB. 64bit OS can still run 32bit (and 16bit) applications.

You can use PAE on 32bit to address above 4GB but that will not work as well as using 64bit.

The 4GB Windows Memory Limit: What does it really mean? - From BrianMadden.com

EDIT - 16bit Apps will NOT run on 64bit Windows (see below)

[Oops_my_bad]

The 32bit version can use (nearly) 4GB total. You have 4x4GB= 16GB so you should definitely use 64 bit or you will waste 12GB. 64bit OS can still run 32bit (and 16bit) applications.

You can use PAE on 32bit to address above 4GB but that will not work as well as using 64bit.

The 4GB Windows Memory Limit: What does it really mean? - From BrianMadden.com

Ah yes, I did come across that, but what isnt clear is if the 4GB memory limit was a limit of XP/2003? I am sort of assuming 2008 ent doesnt have this limitation but I was always under the impression 32bit could only address so much amount of RAM anyway

I have tried the 16bit apps on a 64bit install and they do not work (winlogo, flowol, viewpoint, to name a few. aaagh). The do run OK on 32 though.

[somabc]

Ah yes, I did come across that, but what isnt clear is if the 4GB memory limit was a limit of XP/2003? I am sort of assuming 2008 ent doesnt

You are mistaken I'm afraid, memory addressing limits are controlled by the CPU not the OS. Windows Server 2008 still suffers the same problem. If you do not use 64bit then you are not making best use of your RAM. If you install 32bit you would probably be better taking some RAM out and using it in a different server. Alternatively make this server 64 bit and use either a virtual machine or another Server with 4GB or less to run your 16 bit legacy applications

A 32-bit CPU uses 32 bits to refer to the location of each byte of memory. 2^32 = 4.2 billion, which means a memory address that's 32 bits long can only refer to 4.2 billion unique locations, hence 4GB.

64-bit architecture effectively increases the memory ceiling to 2^64 addresses, equivalent to approximately 17.2 billion gigabytes.

[joe90bass]

The 32bit version can use (nearly) 4GB total. You have 4x4GB= 16GB so you should definitely use 64 bit or you will waste 12GB. 64bit OS can still run 32bit (and 16bit) applications.

You can use PAE on 32bit to address above 4GB but that will not work as well as using 64bit.

The 4GB Windows Memory Limit: What does it really mean? - From BrianMadden.com

I'm interested to know how you get 16bit apps running in 64bit windoze? Like Oops, when I tried our maths progs it was a def no go. I'm literally about to install 3 32bit TS for this reason, if 64bit had worked I may have only got 2 servers running 64bit with more RAM...
I have told our maths faculty that in 5 years time (when our warranty is up on servers and we'll in the market for new ones!) these progs will be history!

[somabc]

I'm interested to know how you get 16bit apps running in 64bit windoze? Like Oops, when I tried our maths progs it was a def no go. I'm literally about to install 3 32bit TS for this reason, if 64bit had worked I may have only got 2 servers running 64bit with more RAM...
I have told our maths faculty that in 5 years time (when our warranty is up on servers and we'll in the market for new ones!) these progs will be history!

Sorry that was a mistake, 16bit apps will not run in 64bit versions of Windows. In 32bit Windows your 16bit apps actually run in a "Windows on Windows" layer. This is missing in 64bit Windows, which instead uses a similar layer called "Windows on Windows 64" to run 32bit apps.

Windows on Windows - Wikipedia, the free encyclopedia
WOW64 - Wikipedia, the free encyclopedia

[DMcCoy]

I'm interested to know how you get 16bit apps running in 64bit windoze? Like Oops, when I tried our maths progs it was a def no go. I'm literally about to install 3 32bit TS for this reason, if 64bit had worked I may have only got 2 servers running 64bit with more RAM...
I have told our maths faculty that in 5 years time (when our warranty is up on servers and we'll in the market for new ones!) these progs will be history!

You can't, unless it's in a VM or other emulation system.

"The 64-bit versions of Microsoft Windows Server 2003 and of Microsoft Windows XP use the Microsoft Windows-32-on-Windows-64 (WOW64) subsystem to run 32-bit programs without modifications. The 64-bit versions of Windows Server 2003 and of Windows XP do not provide support for 16-bit binaries or 32-bit drivers. Programs that depend on 16-bit binaries or 32-bit drivers cannot run on the 64-bit versions of Windows Server 2003 or of Windows XP unless the program manufacturer provides an update for the program."

There is no way to run 16 bit code natively on the x64 versions.

Edit: Too slow! :P

[joe90bass]

Thanks, thought I'd missed out on a trick or workaround there!