I was having the similar problems with 98. Every now and then I needed to do
a clean install and it ran fine for a while and then gradually the problems
came back (other issues such as machine not shutting down etc also began to
appear). I was using 98 Second Edition.

I then changed my operating system to NT 4 with SP 6 and have had no such
problems. Web surfing is now working properly, windows are being refreshed
when they should, no more lock ups and the machine completes it's shut down
process correctly.

I do not know enough about Windows to say whether the problems occurred due
to 3rd party software etc, but from my experience have seen the problems
disappear with a different operating system.

Hope this is of some use to you

Best Regards

David Huisman

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