A member of our seniors computing club has a Duron 900 with 128 meg Ram running win 98 on a 40 Gig hdd.  She says that about three weeks ago it began to run really slowly after about 20 minutes.  She shuts down and waits and then boots up and it is ok but then slows down again. The guy who sold it to her has done all sorts of diagnostics and wants to increase memory  (at a cost) but seems rather vague about what is actually wrong.
I think it might be a heat issue as I understand these Durons run hot.  I had a look inside and the fan is running.  The heat sink feels warm to the touch but not burning hot. I shut it off and the heatsink cooled of in a minute or two. On restart it works really well.  I have removed the side panel and told her to run it like that and see if it solves the problem.
Will installing another fan in the case help?  If so should it blow air into or out of the case?   Alternatively, is there anything else I should consider?
BTW we are a non profit club and share knowledge and assorted help with no money exchange. So we could use some advice on this techy stuff.
Thanks
Rick Thornton

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