Foo - Webpages Start to Load, then Hang, then Eventually Load?

For the past month, one of our computers at work has a problem loading websites previously visited:

--The background, header images, and titlebar title load immediately
--Then nothing happens for about 45-60 seconds
--Then the rest of the page loads normally and quickly


Some fun facts:

--This only happens with websites previously visited and subpages within the site
--Websites that have never been visited load perfectly normal; but when returning to the pages, the problem happens from then on
--I cleared the cache and history but problem persists
--This happens with ALL browsers that I have access to: IE7, IE8, Chrome, FF
--Closing the browser or restarting the computer doesn't solve it
--We have seven computers and the issue is only on one
--Problem happens to all users who log in
--Our IT department says "I don't know, but we can re-image the machine for you." I would rather fix it than re-image due to custom software installs, hotfixes, etc, of course

Ideas? Thoughts? I started Googling but didn't get anywhere. There has to be a simple fix, but I can't think of it right now. :twitchy:

Thanks in advance! (Sorry this isn't a relationship thread. Unless you consider my relationship with the work computers, I guess...)

On a windows PC, I always have fiddler (http://www.fiddler2.com/fiddler2/)handy. It is so incredibly useful for all kinds of connectivity issues. Firebug would probably also find this issue.

Just keep in mind that 200 series codes are goodness. 300 series codes are generally suggestions to the browser (use cache/redirect, et cetera). 400 series codes are errors from the client side. 500 series codes are errors from the server side. See this for specifics (http://en.wikipedia.org/wiki/List_of_HTTP_status_codes).

http://i144.photobucket.com/albums/r162/jsharr/demotivational-posters-you-dont-find.jpg

defrag?

On a windows PC, I always have fiddler (http://www.fiddler2.com/fiddler2/)handy. It is so incredibly useful for all kinds of connectivity issues. Firebug would probably also find this issue.
So, I ran Fiddler, and I get "502" error codes for web pages where I have been before, which hang before they load. I do not get 502 error codes for web pages where I have never been before.

I don't know how to interpret this:

502 Bad Gateway: The server was acting as a gateway or proxy and received an invalid response from the upstream server

Again, this issue only happens on 1 computer in our department; the other 6 computers operate normally. I also want to restate that the headers and backgrounds of webpages load immediately and normally--it's the body content that takes upwards of a minute to load, then it loads all at once as the "502" code shows up in Fiddler.

(I didn't understand of have the time to figure out how to use Firebug.)

A 500 series error is a pretty strong suggestion that the local PC is not the problem or solution.

Do all these computers have the exact same proxy?

One thing you can try is to configure one of the PCs that works normally to use the problem PC as a proxy (basically, you'll set it to use fiddler and the system proxy upstream). My guess is that the same error will begin occurring on the previously fine PC and you will have effectively eliminated the browser from the set of things that could be the problem. You can then start asking questions about what proxies are being used and if there are network caches (http://en.wikipedia.org/wiki/WAN_optimization) or content switches involved.

I will check the when I have time to figure if out, but in the meantime, I used CCleaner on the computer and rebooted it...now, instead of taking ~1 minute to load webpages, it now takes ~3 minutes to load each webpage! Still, brand new webpages load just fine.

I assume it's just a coincidence, but hmph....

A 500 series error is a pretty strong suggestion that the local PC is not the problem or solution.

Do all these computers have the exact same proxy?
I checked the proxy settings and they are unchecked/blank?