Need help with a slow Compaq

I have friend with a Compaq which he is trying to resurrect.
He says it is 300MHz with 3 133M SDRAMs and a 20G HDD
with 90% unused.

He says it will boot up fine and run a while, but then will bog down
horribly. For example, he said he can type several words before they
begin to slowly display, a letter at a time. One such time he had
clicked on a link in an email and was filling in a form to get an
article download from a newspaper site. He gave up.

He uses Eudora and it takes forever to send emails.
His Eudora's task bar shows the emailing sending to completion and
checked it as sent in the out log. Then a Symantec window opens to
show the same thing. Symantec may announce that it was not sent and
give a spurious reason. Or it may just go blank, especially if I have
touched the keyboard. Leaves him with no way of knowing whether his
outgoing email actually went or not. So he turns machinet off.

His phone modem is connecting at various speeds around 45K.

Does anyone have any advice for him besided tossing the thing?

Thanks