Ask Dan: 32 or 64 bit Vista?

Date: 9 February 2007
Last modified 03-Dec-2011.


I wanna grab Windows Vista, but I am unsure whether to get the 32 or 64 bit edition. I have an AMD Athlon 64 3500+, but not the AM2 version. Will it run fine?

Are there any downsides to running in 64 bit at all?

Do 32 bit apps run fine?



There's nothing wrong with your CPU for 64-bit Vista, and it would allow you to install more than 4Gb of RAM, if your motherboard and wallet both support it (though the cheapest "Home Basic" version of 64-bit Vista is artificially limited to a lousy 8Gb). But you probably don't want 64-bit Vista anyway.

[NOTE: This article was written in early 2007. As of a year later, 64-bit Vista works much better. I've updated the text a bit to reflect this.]

The four things that make 64-bit Vista inadvisable for ordinary users are:

1: No compatibility with old 16-bit Windows apps. This means ancient Windows 3.x software, which most people don't run any more, but 16-bit code can still pop up in the darndest places. Like, for instance, in the installer programs for other apps.

2: Various and assorted application compatibility problems. This has improved considerably as of early 2008, but there's still no blanket guarantee that a given piece of software - especially an older piece of software - will work in 32-bit Vista, much less 64-bit.

3: No compatibility with existing 32-bit drivers. Everything on your computer will need a new driver. 64-bit WinXP is the same, and there aren't many 64-bit computers on which Vista won't at least install, but 64-bit Windows also has...

4: No support for unsigned kernel-mode drivers.

There's a good reason for that; bad kernel-mode drivers are probably the number one cause of XP crashes.

But this is still a killer for many users. Most device drivers are kernel-mode drivers, so although a lot of current gear may have a Vista driver at some point (as of early 2008, Vista drivers for new hardware are quite standard), but new drivers for pre-Vista hardware will only ever be 32-bit versions, if the device needs a kernel-mode driver, and the driver team can't be bothered with the driver signing process (which costs money).

They don't have to go all the way to getting WHQL certification for their drivers (so the actual quality of the drivers you get won't, um, actually necessarily be any higher...), but they still can't just write some software and put it on their Web site and have done with it.

This limitation also applies to kernel-mode software other than drivers. Persons unhealthily fascinated by all this can read about it in a DOC file from Microsoft, here.

Apparently you can bypass the signed driver check in 64-bit Vista by hitting F8 and picking a menu option on every single boot (though some people report that even that doesn't work). I presume a better workaround will arrive in due course.

Microsoft provide a Vista "Upgrade Advisor" program that lets you scan your existing (32-bit) XP machine to see how Vista-ready it is.

When you run the Advisor, it'll give you a list of any "cannot find information" devices; those are the ones that may or may not work in Vista, and it's up to you to poke around on the manufacturers' sites to see if you can find a driver.

(I suggest you ignore the Advisor's advice to go to Windows Marketplace, because that just wants to sell you new hardware.)

The computer I'm using at the moment has an nForce4-chipset AMD motherboard, with on-board network and audio adapters. There are 32- and 64-bit Vista drivers now for this chipset, including the network adapter, but not including the on-board sound.

Motherboard manufacturers are releasing their own audio drivers here and there for on-board devices that don't have a driver from the chipset manufacturer, but Vista is generally a bad place for people who like sound at the moment. That's because everything's now required to use the OpenAL API for sound, which has given rise to a spate of new drivers that're really just "wrappers" that translate DirectSound calls into OpenAL, often with unpleasant results for gamers and home-studio people.

There are further software incompatibility problems for Vista, too, but apart from the 16-bit-apps thing they're not specific to 64-bit Vista. They're largely restricted to software that wants to do relatively low-level stuff, like CD/DVD burning programs and programs that tweak system settings.

(And, now that Vista's been around for a while, most software has been updated to get around these problems.)

On my current computer, the only major thing that absolutely will not work (as of early 2007) is my big Epson photo printer, which has no Vista drivers available at all. The on-board sound is also probably a non-starter, but I don't actually use it - I've got a USB audio device, which is fine.

There's really very little reason for home and small business users to upgrade to Vista at all at the moment (February 2007). Yes, it has some nifty new features, but DirectX 10 games aren't quite here yet, and there are still far too many compatibility problems with existing hardware, many of which will be ironed out in the coming months.

There's even less reason for normal users to get 64-bit Windows. Compatibility is even worse, it isn't (overall) any faster for 32-bit software, and unless you already know of some piece of 64-bit software that you really want to run, I can fairly confidently state that there isn't any.

Australian shoppers can buy Windows Vista from Aus PC Market.