citadel - it wasn't intended to be a comment about the relative speed of IE7 and IE8 (should have made that clearer) - as I don't use them, it's irrelevant to me.
The slowdown is not dramatic - it's just slightly, but noticeably, different, and I wondered if anyone else had a similar experience.
My system is far from new - but runs commendably fast for all I do. I've just been surprised at what I think I saw (which is why I repeated it) and wondered whether anyone else had seen a similar effect.
I have installed/deleted/installed IE8 three times, it kept asking me to download as if it had not already been downloaded. I also get message frequently that it "has encountered an error and must close". Still not resolved, I use Firefox as default browser. Cannot find any trace of old programs, Secunia gives me 100%. My system also goes to "sleep" if not used for a while, and is very slow to get up to speed again, there are no power savers or hibernate modes activated, is this because of IE8?