Upgrading to Vista: The Gotchas and the Good News

Computerworld - Most people who make the switch to Vista will likely do so by buying a new computer. But Computerworld readers aren't most people, and they are far more likely to perform their own upgrades with existing hardware.

With previous new versions of Windows, I have always strongly recommended either clean-installing a new version of Windows or just waiting until you're moving up to a new PC. But things are very different with Windows Vista. Microsoft deserves praise for the work it has done on Vista's installation program. It works much better than any of its predecessors, and for several reasons. That change brings about a whole different set of good news and gotchas when considering your Windows Vista upgrade strategy.

The Gotchas

Your biggest problems with upgrading to Windows Vista boil down to these points:

• Real-world hardware requirements
• Upgrade paths
• Cost, both for hardware upgrades and for Windows itself
• Vista drivers and hardware-support software

The truth is that your average late-model Windows XP machine that wasn't of the bargain-basement variety will probably run Vista. The problem is that it might do so at the expense of one of the few primary reasons to upgrade to Vista -- the improved graphical user interface.

There isn't enough that's compelling in Vista to skip this particular improvement. So unless you have a particular reason to install Vista (to test application compatibility, for instance), I recommend against upgrading a machine that doesn't have the right stuff to run Windows Vista's Aero interface. Another option for desktop PCs is to upgrade the video card.

These are the system requirements for Vista that I recommend for anyone's primary or only computer: Intel (or comparable AMD) 1.8GHz (minimum) Pentium 4 CPU, 2GB of RAM, 80GB hard drive (60GB if you're clean installing) and a DVD drive.

In addition, there's a specific set of video requirements that are key for Aero: a DirectX 9 (or better) 3D graphics processor that supports 32 bits per pixel, and Pixel Shader 2.0. It must also be offered with a WDDM (Windows Vista Display Driver Model) driver.

Graphics memory requirements are a little difficult to decipher. I have tested machines with 64MB of video memory that supported Aero just fine, while others with the same amount did not. Graphics cards with 128MB of graphics memory that meet all the other criteria do fine with Aero. But for the best experience, I recommend 256MB of video memory.

It's important to run the free Windows Vista Upgrade Advisor software that you can download from Microsoft. The utility errs on the side of overwarning you; some things you may be able to ignore. But its results cover both hardware and software. Running this program first can make a big difference on your success rate in upgrading an XP installation to Vista.

Be advised about the upgrade paths that Microsoft offers from previous versions of Windows to specific versions of Windows Vista, because some of the limitations may surprise you.