This is pretty low level stuff, but worth checking out.
Right click on "computer" and select properties. On the lower left corner click "performance"
What's your score?
Mine was rated about as low as you can go. 1.0 out of 5.9 and it's a brand new build with close to top of the line gear.
If your score was low like mine, click on the "update my score" link and it will detect your hardware.
WHY, you ask.
It seems to me that Vista thought I had a week system due to this low score and did not turn on all the features it's capable of.
After I ran it I noticed all the small windows (not maximized) that pop up had a transparent edge around them. Also the actions of the windows are a lot more animated when opening and closing. A couple of other things too.
Of course all this is nothing but eye candy and probably takes up even more memory, but I wonder what else Vista was limiting my system to because it did not detect my hardware properly. It gave me a low score in everything but the processor IIRC.
Even after running this updater and you decide you don't want all the eye candy Vista has to offer you can turn it down by selecting "adjust visual effects" on the same "performance" window if you wish. I will probably do just that once I get tired of it.
Anyway. Just thought I'd pass this on.
Check out your score to see if it's low.
If it is update it and see if there are any improvements.
There's a little more to it than one simple score; if you click the Windows Experience Index link next to the number, it'll take you to a subset of scores for different areas. Processor, RAM, 2 sections for Graphics, and your Hard Disc Transfer rate. Each of these has a rating. What you see on the first page is the LOWEST of these 5 scores. Kind of a way to say your comp is really only as good as it's worst bits...
I got a 5.9 in everything except the primary hard disc score. I got a 5.8. IIRC it said something about indexing.
I know it's a good, fast drive (sata, 3.0 gig transfer rate, 16mb cache).
I'll have to see what I can do to improve the Indexing and try again. I had it turned off (via registry) on my last XP machine.
Mostly, I was surprised that Windows, much like a game will load the level of your desktop graphics depending on your hardware.
Also, for me anyway. I had to run this performance tool manually to get an accurate score. If I didn't check it out, Windows would have assumed I didn't have hardware that was up to par with Vista 64 and not have turned on a lot of these features.
It also made me think about what else it may have been hindering. I've been tweaking and overclocking my system and got about 40-50 points higher on 3D Mark after I updated my Vista score.