Vaio SZ Laptop - Slow with Vista and 7 - faster HDD??

It was a clean install, it is not possible to install W7 rtm over W7 RC without hacks.

Although my notebook is a HP Pavillion, so I can not state that experiences will be "identical", a couple of observations?

I installed Win 7 on a 2+ year old HP Pavillion. HP's web site did say that my model was Win 7 capable, however, there was only one actual Win 7 specific driver there to download!

Having said that, it turned out that all the other current Vista drivers were perfectly compatible with Win 7 (64 bit at that!) with the sole exception of the Pavillion's "Quick Start" keys...and as it turned out there was an update from MS for that anyways.

You do not say if your win 7 install was a "clean" or as they now call it "custom" install, or merely an upgrade or not. If you simply did an upgrade, this may be significant, becasue whatever caused your computer to become sluggish in Vista, very likely still exists!

Though Win 7 is lighter on it's feet than Vista, your computer did not "become sluggish" due to Vista, rather there is some software issue somewhere in your system causing this behavior. My laptop does run somewhat "snappier" with Win 7, but frankly, it never ran badly with Vista either...I suspect (but, you never know!) that you have some software conflict somewhere in your system causing this slow behavior.

No offense to any other poster here, but even though a 7200rpm hard drive is a bit faster, that really should not be the problem with your system. Hard drives either run...or they do not, they do not gradually slow down. Sure a faster new hard drive will tweak your overall performance, but in and of itself that will not be a night and day difference...far more likely, and far more cost-effective would be simply to do a clean install. XP, Vista, or Win 7 on a clean install will likely return your notebook to good working order. XP is phasing out, Vista is OK, but definitely a bit pokey, Win 7 really is the "New Sherriff" in town...and I say that as someone who really had no big issues with Vista!

Edit: If this was a clean install, then the next thing that I would suspect would be other programs, particularly programs such as Roxio (older versions), or as in my case, Acronis. When I first went to Win 7, I had frequuent, hard to pin down problems, that turned out to be caused by Acronis 2009...as soon as I deleted Acronis (and replaced it by a very good free disk imaging back up proggie), all the dodgy behavior went away...