Big Questions: The 64-bit Windows FAQ

by Nathan Taylor on Sep 26, 2008

Tags: 64-bit | 64bit | vista | XP | x86-64 | x64 | AMD64 | WOW64

10 Comments

You've been raising some big questions in the forums about 64-bit. Here's our FAQ to 64-bit Vista vs XP, and whether it's worth the hassle if you're not a workstation user, but a gamer or power user.

Which is better: 64-bit Vista or 64-bit XP?
In terms of hardware support there is no question: support for 64-bit Vista far outstrips 64-bit XP. We’re not going to argue aesthetics or interface here, but if you want to be sure of running new hardware on your 64-bit system, Vista is really your only choice. Fewer and fewer vendors are going to release drivers for 64-bit XP, and many didn’t even bother in the first place. 64-bit Vista support, however, while still lagging behind 32-bit, is gradually making its way towards universal.

What desktop PC software is available for 64-bit?
Programs compiled to run in native 64-bit are few and far between. Most are either open source (like Firefox) or professional products (like Adobe’s high-end image and layout tools).

Quite a few utilities have made the jump as well, including SlySoft’s CloneDVD, VMWare and several other popular applications.
Consumer applications, however, including most office suites, productivity applications and games are typically compiled for the lowest-common-denominator: 32-bit (though some, like Crysis, come in multiple versions).

As we’ve mentioned, most of these will work just fine on 64-bit Windows.
If you’re specifically looking for native 64-bit programs, we can recommend these sites, which contain list of compatible programs:
http://www.vistax64.com/software/
http://www.64xsoft.com/
http://www.start64.com/

Can I upgrade my 32-bit Windows to 64-bit?
Nope. The Microsoft installers don’t support that kind of upgrade. You have to back up your files, format your had disk and do a clean install if you want to move to 64-bit Windows.

What does “64-bit” mean, anyway?
You’d think this would be an easy question to answer, but it’s not, because the term is a little amorphous. In the context in which we’re talking, however, it means that the processor can operate on integers of up to 64-bits in size (a 32-bit processor can only operate on 32-bit numbers) and it also means that memory can be accessed using 64-bit addresses (and because you have more addresses, you can have more memory).

It was actually AMD that introduced 64-bit processing to consumer x86 devices when it released the Athlon 64. The Athlon 64 fully supported previous 32-bit programs, but added extra 64-bit capabilities, which AMD called x86-64. These included:

- added 64-bit integer instructions
- expanded the general purpose register count from 8 to 16 (the extra 8 are only accessible in 64-bit mode). Registers are used to hold “current” bits of data for extremely fast processor access. It’s from these additional registers that x86-64 gets its general performance boost.
- expanded the SIMD (XXM/SSE) register count from 8 to 16
- expanded the memory address space from 4GB to (theoretically) 16 exabytes – though current AMD processors “only” support 256TB (that’s 256,000GB).
- The addition of a “No-execute” bit, which prevents common buffer overrun attacks.

Later, Intel joined in the fun, effectively cloning the AMD x86-64 instructions – though it called its implementation EM64T, which it installed in selected Pentium 4-based processors. Now all of Intel’s Core 2 processors support EM64T. Likewise, all current AMD processors support x86-64.

We should make a quick note on the nomenclature here as well. AMD no longer calls its implementation x86-64: it’s officially known as AMD64. Intel has done something similar, abandoning the term EM64T and is now using Intel 64. Most people still use the term x86-64 or simply x64 to refer to the extensions.

10 comments in this discussion

"Gregmond wrote: I wish this arcticle had confirmed if the 64bit was quicker/slower than the 32bit versions - even in basic things like Office, web browsing etc. if the application you are ..."

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Comments: 10

Thoughts on this article? Add a comment below.

.:Cyb3rGlitch:. Sep 26, 2008 5:21 PM	Nice article. I'd recommend Vista 64-bit to anyone with a new PC, it's the best choice. As with any OS, ensure all your hardware and software is compatible first. This is rarely a problem with new PCs. Comment made about the PC Authority article: Big Questions: The 64-bit Windows FAQ? You've been raising some big questions in the forums about 64-bit. Here's our FAQ to 64-bit Vista vs XP, and whether it's worth the hassle if you're not a workstation user, but a gamer or power user. What do you think? Join the discussion.
djaef Sep 27, 2008 9:20 AM	Something to add to the FAQ maybe? Would 64 bit be a better choice if buying a new pc now thinking about the next gen Windows OS? Future proofing has obviously turned out to be a dud concept with computers due to the speed of development, but it does make sense to consider the next version of Windows, especially considering the lukewarm response to Vista.
microUgly Sep 28, 2008 2:14 PM	For now, I would recommend staying away from NVidia hardware if you want to go 64bit. Unfortunately I have both an Nforce motherboard and Geforce graphics cards. The latest Nforce drivers have only just allowed me to play audio CD's through a SATA DVD drive. And I've been living with the inability to play a few popular games due to Geforce driver issues--and new drivers are few and far between. I don't doubt the issues will be fixed eventually, but for now NVidia isn't worth the headache.
.:Cyb3rGlitch:. Sep 28, 2008 2:55 PM	I know many people who use Nvidia GPUs, chipsets, and Vista 64bit with no issues. Perhaps your combo is a dud.
bbjai Sep 28, 2008 6:50 PM	Yeh I think I can't stress enough the need for anyone upgrading to Vista 64 to check your EXISTING peripherals for driver compatibility. Because if you don't you might find alot of things that you currently own don't work with it. Simple small things like a PCI Wireless net card for example. Its still a great system but you gotta factor in replacing these peripherals into the cost too.
OZSlayer Nov 13, 2008 6:18 PM	Cyber did you read the latest edition of PCA? Its proved all my claims when it comes to XP being faster than Vista. lol So how can it be the best OS for new PC when it will run slower than using XP on the same PC. That like saying a motor bike engine work as well in a car as it does in the bike it came out of. Seriously mate smell the roses. Vista in the end is like the DODO, it just going to be extinct soon.
.:Cyb3rGlitch:. Nov 13, 2008 8:23 PM	OZSlayer wrote: Cyber did you read the latest edition of PCA? Its proved all my claims when it comes to XP being faster than Vista. lol So how can it be the best OS for new PC when it will run slower than using XP on the same PC. That like saying a motor bike engine work as well in a car as it does in the bike it came out of. Seriously mate smell the roses. Vista in the end is like the DODO, it just going to be extinct soon. No I didn't read it, I haven't bought it in a while. Slow or not, it's more stable and more secure. If you stick with XP, you're selling yourself short, because Windows 7 is exactly the same under the bonnet. Might as well get used to it now, instead of paying extra for XP. With your reasoning, you could also argue that Windows 3.1 is better than XP, because it's faster. Get with the times, all I.T. professionals recommend Vista out of all the MS range. Otherwise they go with Linux. XP is the Dodo, like it or not. Edited by .:Cyb3rGlitch:.: 13/11/2008 08:27:20 PM
Gregmond Dec 16, 2008 2:41 PM	Now that's an interesting comment Cyb3rGlitch: "all I.T. professionals recommend Vista out of all the MS range." You base this on what ? If you are quoting a company please let me know where they got their data from. I would like to think I am an I.T Professional, and I know the guys I work with are. Some of us use Vista personally (I use 64 Home Premium atm) but there is no way we would even consider migrating our 600+ users to Vista at this time and only one of my coleagues (there are 5 of us) would recommend it to anyone. Why not ? More stable ? maybe. More secure ? maybe - we have some fairly solid infrastructure that does most of our protection. Slower on same hardware ? yes. Hard to understand if you are familiar with XP ? for many users = YES. Offers benefits to corporate users over XP ? Only to deploy, not from users perspective. You may love Vista, I do not. Except that I have a licensed copy of Vista x64 for my home PC and don't have a licensed copy of XP 64bit to try, I would reformat tomorrow. I have also tried several variations of Linux and much prefer them, alas I am a gamer and sometimes games don't work the best under Linux. Hopefully Windows 7 will be an improvement (I believe it will be based on Vista, but we can but hope). I wish this arcticle had confirmed if the 64bit was quicker/slower than the 32bit versions - even in basic things like Office, web browsing etc.
.:Cyb3rGlitch:. Dec 16, 2008 6:04 PM	That's fair enough, if you have lower end systems, then XP is better.
SirSquidness Dec 17, 2008 6:14 PM	Gregmond wrote: I wish this arcticle had confirmed if the 64bit was quicker/slower than the 32bit versions - even in basic things like Office, web browsing etc. if the application you are running is natively 64 bit, then yes, it will run reasonably faster. Most applications aren't though. A lot of programs freely available on the internet or that put drivers in your system have an option for 64 bit systems hidden away. However, it does allow you to address a truck load more RAM, and doesn't limit applications to 2GB of RAM each (and 4GB of address space in total), so if you're running memory intensive applications, there is a chance that singel difference will make a big difference.