This is the third post in my series about the Vista x64 vs. Vista x86 issue. In my first article, I claimed that CPU performance is not really a good reason to jump on the 64-bit bandwagon at the moment. In my last article, I wrote that software compatibility is only a theoretical problem now, and today, I want to discuss hardware compatibility.

Availability of 64-bit device drivers

The fundamental difference between software and hardware compatibility is that most 32-bit apps work flawlessly on Vista x64, whereas 32-bit device drivers are usually useless on a 64-bit Windows. Hence unlike software vendors, hardware vendors have no other choice than to offer 32-bit drivers and 64-bit drivers for their devices. Additionally, only drivers signed by Microsoft will work on Vista x64. This certainly improves security because kernel mode drivers are an attractive target for malware.

The only problem is that Microsoft wants to see money for the signature. Therefore, hardware vendors producing for the consumer market are sometimes a bit reserved about 64-bit. You usually won’t find 64-bit drivers for devices that are older than five years. However, relatively new devices from well-known brands usually support 64-bit. Vista x64 comes with a great variety of drivers, and even more are available via Windows Update.

Testing 64-bit drivers

Unfortunately, it is a bit difficult to make sure that all your devices are supported in advance. Unlike with 32-apps, you can’t test them in a virtual environment because virtualization software such as VMware Workstation or VMware Server emulates different hardware for the guest OS. The only exceptions are USB devices. If the mouse focus is on the virtual machine, VMware will automatically redirect devices connected at the USB port to the VM.

You can also check your hardware vendor’s support site, to make sure that 64-bit device drivers are available. However, often you’ll only find Vista drivers without any further notice regarding 32-bit or 64-bit. Sometimes the downloadable package contains 32-bit and 64-bit drivers. So, often the only way to find out if all drivers are available is to just try with real hardware.

If you plan to deploy Vista x64 in a corporate environment, you should have at least one test PC for every model in your network. If you have no other choice than to test it on the target PC, I would just add another partition or hard disk and install Vista x64 as second OS. This way, you can still go back to your original 32-bit installation. Note that you have to start from scratch anyway, because there is no upgrade path from Vista x86 to Vista x64.

You could also install Vista x64 on an external USB disk, and try it on the different PC models in your organization. The first thing that you want to check out after Vista boots up is the Device Manager. I hope you won’t see too many question marks there.

Conclusion

Unlike software compatibility, hardware compatibility is still problematic with Vista x64. However, the situation is much better than it was one year ago. Therefore, if you desperately need more RAM than 3GB, and if all your hardware is relatively new, you should give 64-bit a chance.

Security might be a reason to move to Vista x64, too. However, Vista x86 is already a very secure operating system. Thus, better security alone is not really argument for 64-bit. The signed device drivers also improve the reliability of the OS. However, the reliability of your applications will be lower, since you’ll have to run 32-bit apps on a 64-bit OS, which can cause problems.

Vista x64 is certainly not an advisable option for typical office PCs in a corporate environment. A secretary will most likely not type a letter faster, just because her or his Word runs on a 64-bit OS. That additional trouble Vista x64 might cause doesn’t make a move to 64-bit worthwhile in most cases. 32-bit will dominate the desktop world until Windows 7 comes out. There is a good chance that 64 is the default bit-length on new PCs by 2010.