64 bit has finally arrived ... but not really | The Coffeehouse

Heywood_J
Trust me, I'm from the Internets

For a long time I've complained that 64 bit CPUs and operating systems have been available for many years but the lack of 64 bit applications and drivers has made it pretty much meaningless. We're stuck plodding along with our 32 bit Windows XP.

So now I'm noticing quite a few computers from well known companies (Acer, HP, etc.) that are being sold with Windows 7 x64 installed. Cool!! They finally "get it". But then I start looking more closely at the specs for these computers (thanks to Newegg who gives lots of info about everything they sell) and in every case I find the same thing: 2 memory slots -- maximum memory supported 4 GB.

WTF?? What's the point of a 64 bit OS if you're going to put it on a computer that effectively limits you to the same 4 GB as Windows XP/2000. I don't get it.

jon_potter
jon

A couple of points off the bat:

1. Windows XP/2000 (32 bit) only supports 3.something GB of physical RAM, not 4GB.

2. Even with only 4GB of physical RAM, the virtual address space of each process is much larger, which may be useful in some cases.

ManipUni
Proving QQ for 5 years!

- 32 Bit computers cannot support 4 GB of RAM

- 32 Bit computers cannot support 64 bit applications (64 can support 32 bit)

- 64 Bit CPUs have a better instruction set

- Going 64 bit with no benefit is still a benefit, since you lose nothing

So I cheer these 64 bit 4 GB computers. I hope Dell, HP, etc, simply stop selling desktops without 64 Bit OS's on.

Sabot
My name is Dave Oliver. I'm a Technical Architect.

In reply to ManipUni

#Oct 23rd @ 5:31 AM

Over in the Enterprise and Server World the move to 64bit has pretty much happened, infact many Microsoft products are feeling safe enough to go 64bit only such as Exchange (2008 and 2010) , SQL Server (2008 R2) and Windows Server (2008 R2)

I'm a firm believe that if you are targetting these environments with your code you should be developing in them, so yes my laptop is running Windows 7 32bit RDPing on to my development environment which is a 64bit Windows 2008 R2 environment running SQL Server 2008 and Visual Studio 2008.

I do little else with my laptop OS than run Office and the Web and 32bit is fine for that. I see no reason to take Visual Studio around with me, the Wireless and 3G card in my laptop means I can get at my 64bit dev env if I need to. And as my Dev env is a VM I can have as many copies as I like, add and take away CPU's and memory at a whim.

LeoDavidson

64-bit Windows is definitely not a red herring, even on machines with only 4GB of RAM.

Both my desktop and my laptop have 4GB RAM, but when they had 32-bit Windows on them much of it was wasted.

The desktop was the worst since my hardware, including a 750MB graphics card, ate an almost 2gig chunk of the address space. I could only use just over 2gig of the RAM I had. (I bought the other 2gig recently in anticipation of the move to Win7 64-bit.)

figuerres
???

check the max ram specs... some times they will show that the pc has 4 gigs installed but you can takr that out and put in 8 or 12 if there are sticks that have the ram on them ...

like right now i have a box with 12 gigs but i bet when a new generation of ram modules comes out i will be able to do 24 gigs *if* i wnated to.... no plans for that but it's possible if the memory sticks are made with enough chips per stick.

wkempf

In reply to figuerres

#Oct 23rd @ 6:58 AM

Yeah, I thought the same thing. Quick look at Newegg, and I find several HP's that ship with both Win 7 64 bit and Vista 64 bit, which already brings into question his assertion that there's been a lack of support for 64 bit from vendors in the past. In every machine I've found, Vista or Win 7, there's not only been 4 slots and larger than 4 GB capacities, but there's been more than 4 GB installed. So, even assuming I've missed something, it's pretty obvious that there's not a trend to install Win 7/Vista 64 bit on machines that only support up to 4 GB.

CreamFilling512

On the flip side if you have 2 or less gigs I'd install 32bit. 64-bit does consume more memory, and disk space. 3 or more I'd definitely use 64-bit though, especially if you have a fancy video card.

Ion Todirel
buuu

o_O build your own machine?

Bass
www.spreadfirefox.com/5years/

In reply to jon_potter

#Oct 23rd @ 5:25 AM

32-bit, no-PAE processor supports up to a 4 GB address space.

Address space != memory, although memory consumes address space equivalent to it's capacity.

You can't easily predict how much memory a computer will allow in 32-bit mode, since it's depedent on the mobo, video card and possibility of other peripherals and their consumption of address space.

magicalclick

Not sure what to say. Choose more expensive models? If you have a dedicated graphics memory, 4GB is more than enough. If you want something more than that, just buy the gamming machine or something.

dentaku

I've found that almost everything HP and sometimes Toshiba sells has 64bit Vista on it and I'm assuming the trend will just keep getting bigger now that Win7 is out. Most Core i7 (gaming) systems have 6GB.

Bas
It finds lightbulbs.

In reply to dentaku

#Oct 24th @ 5:02 AM

I was checking out consumer laptops from Dell and all came with x64 only. 4GB was the minimum. Looks like the consumer switch is happening too.

PaoloM
Hypermediocrity

In reply to Bas

#Oct 24th @ 5:06 AM

So yeah, I still have 32bit Smiley

I do have a E6600 and 4Gb RAM, so what exactly would x64 give me, considering i'm running mostly Office (2007 , 32bits), VS2k8, Expression 3?

ManipUni
Proving QQ for 5 years!

In reply to PaoloM

#Oct 24th @ 11:47 AM

Fair enough.

But if you could get 64 bit for "free" (e.g. You're buying the computer / reinstalling W7 anyway) then there is no good reason not to.

PaoloM
Hypermediocrity

In reply to ManipUni

#Oct 24th @ 11:53 AM

I am not trying to antagonize or anything Smiley . I was just wondering if there are actual benefits *for me* in running x64, cause I've always been a bit unclear on that aspect...

ManipUni
Proving QQ for 5 years!

In reply to PaoloM

#Oct 24th @ 12:04 PM

You can compile into 64 bit and test your programs.

joechung

In reply to ManipUni

#Oct 24th @ 12:14 PM

You don't get a 64-bit operating system to compile programs into 64-bit with Visual Studio.

Being able to run 64-bit programs is a practically tautological reason to install a 64-bit operating system.

ManipUni
Proving QQ for 5 years!

In reply to joechung

#Oct 24th @ 12:26 PM

He asked what *he* would benefit from running a 64 bit OS. Testing applications that he might need to compile for 64 bit OS's is one that would benefit him. It might be another way of saying - "supports 64 bit applications" but yet it has more validity to him personally since there aren't very many applications right now which are only shipped as 64 bit binaries and nothing else.

If you're a C++ programmer in particular and want to ship 64 bit binaries you're a fool if you aren't testing them. You cannot assume that because it all works on 32 that the same is true with 64.

Bas
It finds lightbulbs.

In reply to PaoloM

#Oct 24th @ 11:47 AM

No idea. I decided to go 64 bit for my desktop PC (laptop doesn't seem to support it), and I can't say I'm blown away by the speed increase or anything. I can't say it's worth it yet on a user level, but it looks like the major PC manufacturers are switching for their consumer PC's now too, so when it'll become worthwhile, it'll maybe be common enough already.

LeoDavidson

In reply to PaoloM

#Oct 24th @ 12:04 PM

You'd be able to use all of that 4gig if you switched to 64-bit Windows. Chances are at least some of it (and potentially a lot of it) is unusable due to hardware eating a hole in the address space.

(e.g. I could only use just over 2gig of my 4gig before switching to 64-bit.)

If you open Task Manager and go to the Performance tab, the Physical Memory - Total value is how much of your RAM the OS can actually use. (Use Task Manager to check, not the System control panel. The System panel says how much RAM is in the machine, not how much can actually be used by the OS.)

FWIW, for testing apps on x64 you can use VMware to run 64-bit Windows under 32-bit Windows. I used to do that until switching to Win7 and 64-bit on my main dev machine.

PaoloM
Hypermediocrity

In reply to LeoDavidson

#Oct 24th @ 2:29 PM

Hrm, that makes sense. I am not feeling any memory pressure issue now, but I can see this being something to think about when VS2k10 is released.

Thanks guys Smiley

figuerres
???

In reply to PaoloM

#Oct 24th @ 9:26 PM

I seem to recall that each 32 bit app on windows 64 bit os gets it's own virtual 4 gigs of address space.

so that even 32 bit apps do get a benefit. they do not have to share the same address space.

and if you have any large apps that use a gig or more of "real" address space then with the x64 os you can run them w/o forcing somethings to page out to virtual space.

say you have 2 apps that each need 2 gigs of actual address space and you have other apps that need a half a gig each.

plus the os needs a chunk...

with x32 the apps would have to use virtual space and page in and out to all run at one time.

with x64 the wow layer can allocate each x32 app it's own space out of the x64 address space.

so if you have enough total ram you can run all the apps w/o paging them.

at least this is how i seem to have read that it works.

Sven Groot
My name has 9 letters. Coincidence? I think not...

In reply to figuerres

#Oct 25th @ 1:33 AM

A 32 bit app on x64 will get 4GB virtual address space but only if the application is marked as large address aware (it's a flag in the PE file).

The second part of your post is wrong. It seems you don't understand how address space works. On x86, each app gets 2GB user mode address space. This is totally independent from any other app on the system. It doesn't matter if you have a billion apps running, they all get 2GB address space and it doesn't matter how much RAM you have.

If multiple apps actually commit 2GB of RAM, then you would start to swap because not all of those committed pages from all the apps can be held in RAM. But that would happen on x64 too as well if you don't have enough RAM. The 64 bit address size, nor how the virtual addresses are mapped to physical addresses, have little influence on this situation, only how much physical RAM you have matters. Of course, on x64 you can have more memory so swapping wouldn't be needed if you have enough of it.

"with x64 the wow layer can allocate each x32 app it's own space out of the x64 address space."

That sentence just doesn't make any sense at all. Applications don't get allocated physical addresses, that is done on a per-page basis and is subject to physical memory availability.

figuerres
???

In reply to Sven Groot

#Oct 25th @ 2:20 AM

badly written perhaps but i do undestand how it works...

what i was trying to get accross was this: if you have say 5 gigs of apps (each using less than 2 gigs) and 32 bit windows you have to swap. i am saying that 5 gigs is needed of actual address space not virtual.

but if you have a 64 bit windows and more than 5 gigs of ram say 8 gigs and you run the same 32 bit user mode apps.

then they each get a slice of the total ram and will not need to page if the system has enough ram for all of them at one time.

does that sound better Sven?