There are several time servers available. I "THINK?" I got mine when I loaded Net framework and had to be sync'd with the server. Right click on the clock time on the right side of your start bar. If it's installed you should see a third tab called "Internet Time" on the properties window. You can enable this automatically or if you have a dialup connection just click "update now" when the connection is active. This will set your computer clock to within a second of the atomic clock.

If you distrust Billy the Borg you can get the software directly from NIST (National Institiute of Standards and Technology) at this website.

http://tf.nist.gov/service/its.htm

If your computer time is faster than the server you are looking at, your computer may decide that old pages in your cache are newer than the things you are looking at and not update your pages.