said by msmisfit:How old is your router?
This is totally irrelevant, but my friend in Wisconsin has a ZyXel router that she's having problems with on another ISP [she works for]. She's decided to update her router having found no other reason for her problems. Sorry I don't know the model.
Another question might be how old is the computer? Sounds exactly like the the 2 REAL old ones I have upstairs. Both are running Windows 7, but were originally XP machines.
Neither do that pulsating thing real bad when using IE, but when using any other browser, it's real bad. I've even tried new network cards, but no difference. My router and switches are all modern enough to handle the 30/4 plan I'm on.
Been going to post just about this same exact question because of those 2 machines for quite some time.
I decided to try dual booting one computer and installed that bloatware Ubuntu. Amazingly, that computer runs MUCH sweeter using it! Still pulsates some, but not nearly as bad. My speed doesn't fluctuate like yours but any progress bar or anything similar on a speed test, is still a little herky jerky.