Server CPUs 32-bit vs. 64-bit

[nickboutalas]

Hi there,
I have been looking for the past few days at server cpus and I wanted to ask why are server cpus base on a 32-bit system and why not a 64-bit

 

[drixkarasu]

What CPUs are you talking about?
Modern Xeon/Opteron CPUs support both x86 and AMD64.

 

[spdragoo]

Intel server CPUs have been 64-bit since the 2004 revision of the Netburst-based Xeons. AMD server date slightly earlier, with the first 64-bit Opterons coming out back in 2003.

Doesn't mean that they can't run 32-bit Windows Server, or that some companies might choose to buy/sell them with a 32-bit OS instead of a 64-bit OS, but that's more of a marketing than a technical decision.

 

[Karsten75]

Unless we talk archaic software, I cannot conceive of a circumstance where a server will benefit from 32-bit processors or software. As has been remarked multiple times in prior responses, for many years now all Intel, AMD, and most other processors and chips have been at least 64-bit capable in the server market.

 

[nickboutalas]

No I mean that AMD Opterons are a x86 Server cpu as AMD says.but i don't understand why they dont build x64 based cpus for servers.

 

[Karsten75]

No I mean that AMD Opterons are a x86 Server cpu as AMD says.but i don't understand why they dont build x64 based cpus for servers.

I think you're mistaken. Opteron was introduced with both native 32-bit and 64-bit support.

http://www.cpu-world.com/CPUs/K8/TYPE-Opteron.html

http://en.wikipedia.org/wiki/Opteron#Two_key_capabilities

Opteron combines two important capabilities in a single processor:
native execution of legacy x86 32-bit applications without speed penalties
native execution of x86-64 64-bit applications

 

[spdragoo]

The only "pure" 64-bit CPUs are Intel's Itanium line (previously known as IA-64). The problem is that, since they don't have 32-bit instructions, they rely on a built-in "virtualization layer" to run legacy 32-bit server apps...& Microsoft stopped supporting them after Windows Server 2008 R2.

Again, though, all Opterons & all Xeon processors for the past 10+ years have been "64-bit", because they have the 64-bit instruction sets in them that let them utilize a 64-bit OS. That's why, whenever you run one of those "can I upgrade to this OS?" apps on older "32-bit" CPUs, they tell you that you can't use the 64-bit version of the OS: those older CPUs only have 32-bit instruction sets on them, so they can't run a 64-bit OS.

 

[jsmithepa]

As noted 64bit is been around a while.

My guess is, this particular vendor got a very highly discounted batch of 32bit CPU and that's what he used, which maybe good enough for the application on hand.




An Amusing Anecdote:

The first PC ever made in 1974 was the famed IMSAI which sit on a S100 BUS. People would often ask, why S100? why not this and that, why S100 made it such a good choice? One day the inventor fessed up: Because at the time the military had a surplus of S100 boards.

Sometimes, my friends, there are no cosmic, ethereal, God-given reasons, it was just...

 

[gamerk316]

x64, or AMD64, is simply an extension to the x86 instruction set. Most CPUs are marketed as x86 for that reason, but pretty much all of them have had 64bit support since 2004.