FC5 strange Mozilla rendering slowness

[Dean S. Messing]

I have a strange mozilla problem.

When I go to <www.adobe.com> on my FC5 machine (running mozilla 1.7.13)
it takes forever and a day to render the page. I've tried it with
plugins installed (in particular flash and java) and with no plugins
at all.

gkrellm says that the bitrate is piddling: a few KB/s (like 4 or 5)
for many seconds.

On an older mandrake machine running Mozilla 1.7.2 that sits right
next to the FC5 machine and on the same hub, the rendering is
fast.  And I see a corresponding speedup of the bits coming in.
gkrellm shows the rate at around 200KB/s for a second or two.

On the other hand the FC5 machine seems to be able to download large
files via mozilla quite well.  I see data rates of 200KB/s or more.
And, furthermore, I don't have any other network slowness on the
machine.  

I'm completely stumped. What could this be?

Dean