X2 amd or Core 2 Duo require 64 bit OS?

morkys · Post by **morkys** » Sun Jan 18, 2009 11:04 am

I have a 939 based 3000+ AMD64 PC with Windows XP Pro SP2. If I change my platform to AMD AM2(+) or Intel 775 Core 2 Duo...do I need a 64 bit OS..or is a 64 bit OS preferable vs what I have now?

nutball · Post by **nutball** » Sun Jan 18, 2009 11:11 am

You don't need a 64-bit OS, 32-bit XP will run just fine with them.

If you want to exploit those CPUs ability to address more than 4GB of memory you'll need a 64-bit OS though (32-bit XP won't see more than 3GB even if you fit more).

morkys · Post by **morkys** » Sun Jan 18, 2009 12:26 pm

What 64 bit OS is there? Windows XP Pro in 64 bit? Vista?

nutball · Post by **nutball** » Sun Jan 18, 2009 1:05 pm

There is a 64-bit version of XP, but it's not well supported with drivers in my personal experience. Vista is available in 64-bit and works pretty well, Windows 7 will doubtless be better, and of course there's Linux

morkys · Post by **morkys** » Sun Jan 18, 2009 1:45 pm

Gotcha. I've heard good and bad things about Vista. What's the short and dirty on that one? What do people like, and what do people dislike? I have no problems with XP Pro SP2. I suppose I could always stick to 2 GB of dual-channel or 3GB of ram, which ever proved faster.

tehfire · Post by **tehfire** » Sun Jan 18, 2009 3:15 pm

Quick and dirty is that Vista is good in terms of taking advantage of new technologies (gaming, processors, etc.), but it can be a bit of a resource hog. Make sure you have at least 2GB of memory and you should be fine. Also, it may seem a little sluggish at bootup as it loads many programs and such. Windows 7 I have heard is better in this regard.

maf718 · Post by **maf718** » Sun Jan 18, 2009 4:06 pm

32 bit windows XP can utilise 4 GB of physical memory but will not see all of it due to video card memory, system ROM, PCI cards etc which use up some of the address space, which is limited to 4GB.

I have XP 32bit (with all service packs and updates) on an Intel socket 775 system and Windows sees 3.5 GB of the 4 GB installed in my system. If I installed a graphics card with 1 GB of memory rather than the 512 MB I have, I guess it would go down to 3 GB. With memory prices for 2x2 GB kits as low as they are now it is sensible to keep your XP pro 32bit even if it won't see 512mb or so of the installed ram.

If you need to buy a new OS anyway, there is no reason not to get Vista 64bit, but if you can re-use your current OS don't let the 4 GB memory support issue put you off. In my opinion there is no need to upgrade to a 64bit operating system unless you want to use more than 4GB of memory, including whatever video card memory you have in your system. Obviously if you want 2x 1GB graphics cards in crossfire or SLI and 4GB of system memory you will need 64 bit Windows.

A new OS is expensive, don't buy one if there is no need.

morkys · Post by **morkys** » Sun Jan 18, 2009 8:54 pm

maf718 wrote:32 bit windows XP can utilise 4 GB of physical memory but will not see all of it due to video card memory, system ROM, PCI cards etc which use up some of the address space, which is limited to 4GB.

I have XP 32bit (with all service packs and updates) on an Intel socket 775 system and Windows sees 3.5 GB of the 4 GB installed in my system. If I installed a graphics card with 1 GB of memory rather than the 512 MB I have, I guess it would go down to 3 GB. With memory prices for 2x2 GB kits as low as they are now it is sensible to keep your XP pro 32bit even if it won't see 512mb or so of the installed ram.

If you need to buy a new OS anyway, there is no reason not to get Vista 64bit, but if you can re-use your current OS don't let the 4 GB memory support issue put you off. In my opinion there is no need to upgrade to a 64bit operating system unless you want to use more than 4GB of memory, including whatever video card memory you have in your system. Obviously if you want 2x 1GB graphics cards in crossfire or SLI and 4GB of system memory you will need 64 bit Windows.

A new OS is expensive, don't buy one if there is no need.

Right. I would use a motherboard with onboard video, very little if any gaming. Would the onboard video use the system ram? That would cause me to lose even more memory.

What is the difference between seeing and utilizing. I mean, if the system runs with 4 GB installed but windows only sees 3 - 3.5 GB ..how can I make use of that memory. It has to be address-able to be utilized, right?

maf718 · Post by **maf718** » Sun Jan 18, 2009 10:36 pm

yeah, I didn't explain that perfectly, but the physical address space is limited to 4GB. When everything else has been allocated the address space left over can be used for system memory, in a typical system this is often 3.5 GB. This is the amount of memory that Windows can see and use, and is indicated in system properties.

In my system, for example, 0.5 GB of RAM is unused by Windows XP but it is nothing to worry about. I could have just installed 3.5 GB of ram instead but it would have been more expensive than 4 GB and probably wouldn't have worked in dual channel mode properly.

nutball · Post by **nutball** » Mon Jan 19, 2009 12:26 am

The only nit with Vista 64 is that sometimes driver development can lag a bit compared to Vista 32. The major components like graphics cards, mobo chipsets and so on are generally fine, but if you've got hardware or software from smaller companies then Vista64 comes down their list of priorities.

My DVB-S TV card for instance, the Vista32 drivers are "stable" whereas Vista64 are still "beta". Likewise the authors of Speedfan and RMClock have been tripped up due to the driver-signing requirements in V64 (this situation has now been fixed, but illustrates the point -- for a while getting either of those two to run was a fair bit more complex than on V32).

The situation with V64 seems a lot better than it did when I used XP64 though. Right now though if you don't need >3.5GB then stay 32-bit, and if you're going to do that you may as well stay with XP. With Windows 7 looming later in the year an upgdare to Vista now doesn't look attractive unless it's essential for some reason.

Strid · Post by **Strid** » Mon Jan 19, 2009 1:44 pm

nutball wrote:The situation with V64 seems a lot better than it did when I used XP64 though. Right now though if you don't need >3.5GB then stay 32-bit, and if you're going to do that you may as well stay with XP. With Windows 7 looming later in the year an upgdare to Vista now doesn't look attractive unless it's essential for some reason.

If you're satisfied with Windows XP, why don't you stick to it? Works perfectly fine and there's no real benefit by going Vista anyway. I don't see no real reason to use 64-bit OS, when 32-bit generally have better support for drivers and so on.

With that said, I personally use 64-bit Linux, but I still have 32-bit Windows XP as a secondary OS. I can't see myself going over to Vista - not before Windows XP is as outdated as Windows 3.11 is now.

m^2 · Post by **m^2** » Tue Jan 20, 2009 9:43 am

maf718 wrote:If you need to buy a new OS anyway, there is no reason not to get Vista 64bit

All reasons not to buy Vista are valid with Vista x64 too.

maf718 wrote:In my opinion there is no need to upgrade to a 64bit operating system unless you want to use more than 4GB of memory, including whatever video card memory you have in your system. Obviously if you want 2x 1GB graphics cards in crossfire or SLI and 4GB of system memory you will need 64 bit Windows.

A new OS is expensive, don't buy one if there is no need.

Agreed.

I use XP x64 for almost a year. It has indeed lower drivers support than XP and probably worse than Vista too. Some system related software (like some antiviruses) may have issues too.
But overall it's a very good system, after the switch from 32 bit XP you'll feel at home. If you check for drivers before buying hardware, I can heartily recommend you this system. And myself I'm not switching soon, at least until W7, likely longer.

QuietOC · Post by **QuietOC** » Tue Jan 20, 2009 11:40 am

nutball wrote:If you want to exploit those CPUs ability to address more than 4GB of memory you'll need a 64-bit OS though (32-bit XP won't see more than 3GB even if you fit more).

You don't need x64 to support >4GB of RAM. Since the Pentium Pro was released x86 processors have been capable of addressing 36-bits of memory using PAE mode. Apple's OSX is a 32-bit x86 OS that can address much more memory than you can install into a Mac Pro. OSX also does the neat trick of running 64-bit apps on a 32-bit OS, but 64-bit OSX apps are still very rare.

Microsoft has somewhat artificially limited desktop versions of 32-bit Windows to <4GB. The real problem was lack of 64-bit drivers. PAE mode drivers for x86 use the same 64-bit addressing as x64 drivers.

nutball · Post by **nutball** » Wed Jan 21, 2009 2:59 am

QuietOC wrote:
nutball wrote:If you want to exploit those CPUs ability to address more than 4GB of memory you'll need a 64-bit OS though (32-bit XP won't see more than 3GB even if you fit more).
You don't need x64 to support >4GB of RAM. Since the Pentium Pro was released x86 processors have been capable of addressing 36-bits of memory using PAE mode. Apple's OSX is a 32-bit x86 OS that can address much more memory than you can install into a Mac Pro. OSX also does the neat trick of running 64-bit apps on a 32-bit OS, but 64-bit OSX apps are still very rare.

Microsoft has somewhat artificially limited desktop versions of 32-bit Windows to <4GB. The real problem was lack of 64-bit drivers. PAE mode drivers for x86 use the same 64-bit addressing as x64 drivers.

Sure. Way back when I had an 8-bit machine with 128K RAM and 128K ROM. All sorts of fun are possible. In practice though if you want to run Windows in a home environment with >4GB RAM without faffing about, V64 or XP64 are the only meaningful choices.

Mats · Post by **Mats** » Wed Jan 21, 2009 6:25 am

morkys: I'd say keep using XP until windows 7 shows up.
We're only talking about 9 months anyway, and you'd never notice that you only have 3.4 of 4 GB RAM available during those months,
it's still much faster than your current system. And don't get anything less than 2 x 2 GB.

Read this about Vista.

RedAE102 · Post by **RedAE102** » Tue Mar 03, 2009 3:51 pm

For a desktop with 3GB or more RAM, I would heartily recommend Vista x64. I run Vista Ultimate x64 on my main desktop, and couldn't be happier with it. It can take some time to start up, but my desktop is typically on 24/7, so that really isn't an issue for me. For laptops though, 7 is worth the wait. I'm currently running 7 Beta x64 Build 7000 (the public beta) on my laptop, and am very happy with it. I get at least as much battery life from it as I did with XP (it came with Vista), and it is much lighter on resources than Vista x64 was (actually, 7 x64 runs about the same memory usage as Vista 32-bit did!). 7 boots in 40 seconds on my laptop. Because of this, I no longer need hibernation or sleep mode (neither of which work properly with 64-bit Vista/7 anyway due to a BIOS issue). The laptop specs: Athlon X2 TK-57 1.9 GHz, 4GB DDR2-667 4-4-4-12 RAM, Hitachi 7K320 320GB 7200rpm HDD, and AMD RS690M (mobile 690G/SB600). In a nutshell: for a laptop, or someone who needs their system to boot quickly, 7 is worth the wait. Otherwise, Vista x64 is great if you have the RAM for it.

incorrect · Post by **incorrect** » Tue Mar 03, 2009 9:16 pm

i've been loving xp x64 so far. but i'm starting to feel like this is the end of the road for windows on my home pc.

when open source drivers for 3d hardware reach some level of day-to-day-use stability, i'll go for a linux distro running whatever kde they're up to and a nice shiny new version of wine.

i just don't like where i see windows going. i've never liked linux all that much, but at the rate it's being polished i think another two or three years is all i'll need to jump over.

in relation to the topic, there's no real need i can think of to run a 64-bit os right now - there aren't any real killer apps that aren't also available in 32-bit versions with at most a 10% speed penalty. if you have 3+ gb of ram or are big into encryption benchmarks, go with 64-bit. otherwise, flip a coin.

Aris · Post by **Aris** » Wed Mar 04, 2009 8:54 am

nutball wrote:(32-bit XP won't see more than 3GB even if you fit more).

32-bit XP will see 4gb. The reason you "see" less is because it takes into account the amount of shared memory for onboard graphics as well as memory on dedicated graphics cards.

So if you have a 512mb graphics card and 4gb of memory, windows see's 3.5gb of memory.

If you have a 1gb graphics card and 4gb of memory, windows see's 3gb of memory.

Its 4gb of total memory on the buss, not just the memory plugged into your ram sockets.

m^2 · Post by **m^2** » Wed Mar 04, 2009 11:12 am

incorrect wrote:i've been loving xp x64 so far. but i'm starting to feel like this is the end of the road for windows on my home pc.

when open source drivers for 3d hardware reach some level of day-to-day-use stability, i'll go for a linux distro running whatever kde they're up to and a nice shiny new version of wine.

i just don't like where i see windows going. i've never liked linux all that much, but at the rate it's being polished i think another two or three years is all i'll need to jump over.

Exactly the same here. Except that I feel it for more than a year already and I'm not moving soon, I'll keep using XP x64 as long as it's feasible and then decide what to do next... I really don't trust in Wine and over the years I made my Windows environment fit my needs so well...as a noob, w/out all my tools I'm gonna loose a lot of productivity and overall comfort of usage.

incorrect · Post by **incorrect** » Wed Mar 04, 2009 11:25 am

m^2 wrote:Exactly the same here. Except that I feel it for more than a year already and I'm not moving soon, I'll keep using XP x64 as long as it's feasible and then decide what to do next... I really don't trust in Wine and over the years I made my Windows environment fit my needs so well...as a noob, w/out all my tools I'm gonna loose a lot of productivity and overall comfort of usage.

well you can always wait 5 years for reactos

or use it today and age rapidly

Mats · Post by **Mats** » Wed Mar 04, 2009 11:32 am

Aris wrote:So if you have a 512mb graphics card and 4gb of memory, windows see's 3.5gb of memory.

If you have a 1gb graphics card and 4gb of memory, windows see's 3gb of memory.

Its 4gb of total memory on the buss, not just the memory plugged into your ram sockets.

Partly true, but you won't get 4096 - 64 MB ram out of a 4 GB W32 desktop system if you use a 64 MB video card.