About two weeks ago, my machine started to behave real strange: it boots normally, gets to the welcome screen (which it should't, cos there's only one account),plays the welcome music and takes 20 MINUTES (sic!) to get to the desktop. From there on, the machine works flawlessly.

I've tried everything you could imagine. Today I've been reading the posts around and have tried a couple of tips, but to no avail.

The only things I've have booting is zonealarm and F-prot antivirus (I uninstalled them for a while looking for the culprit). WXP pro is updated, have searched for virus, trojans and such. Have updated the bios in despair, played around with the services, installed a ton of tweaking / diagnosing programs to get the source, searched the web, but no results.
Ann MANY other things I can't even remember...

I'm at loss. ANY help appreciated.
TIA

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Wxp pro
AMD XP 2400
ATI radeon 7000
80 GB
512 MB