The screen on my ThinkPad T20 got too pink and the 256MB of RAM just didn't cut it. I came across a T42 on RetroBox and went for it. It's 1.7GHz and 1GB or RAM. Much better.
The first question was go to Vista or not? Sure, why not?
I installed Vista Home Premium using the clean install from an upgrade DVD. Worked like a charm and quick, taking about an hour and a half.
Vista didn't find a video driver. No problem, I thought. Windows Update will fix that. Nope. No driver there. No problem, I thought. It was an ATI Mobility Radeon 7500 so off I went to the ATI site. Nope. No driver there. No problem, I thought. Off to ThinkWiki. Nope. No driver there. Problem.
I finally found a post on Microsoft's TechNet forum that gave a bizarre workaround but it worked. Kinda.
This gave me most of the expected features and controls for the video adapter but, alas, no Aero. Seems that the 7500 doesn't have Pixel Shading 2! So close, yet so far.
I ran through much of my normal install process and went to connect to my server where my printers are. No go. Vista said the print spooler wasn't running on the XP system. But it was. Fiddle, fiddle, and suddenly without explanation they worked.
In summary, that's how the whole experience went. What was expected to work didn't. Sometimes there was a fix or workaround and sometimes there wasn't.
Just to get a sense, go to Lenovo's "Drivers and software" page and note the dearth of support for Vista. Missing are items like Audio (worked), Trusted Platform Module (TPM), Intel SpeedStep Applet, Intel Chipset, Presentation Director, LCD/Monitor, and of course ATI Radeon/FireGL. Some of these could be included in the Vista base code.
That got me to thinking about what Alex Rublowsky of Microsoft had told me in an Executive Briefing in Redmond November 3, 2005 - "When Vista ships, 3 year old systems will run it." Not even close. And this T42 is an enterprise class system built in August 2004.
In the end, I punted and went back to XP Pro. Felt like an old pair of shoes.