Ok, since you only want to guess and not troubleshoot to rule out issues, please post the discovery when the issue is finally resolved. Good Luck!

Well, the last idea that I have is to look at the router settings for the internal firewall. Or perhaps, that one network adapter with Windows 7 drivers doesn't play well with the router. Try, rebooting the router. Check the firmware version and update the router firmware if available. Don't forget to export the configuration settings if needed. Finally, look at the firewall settings.

If safe mode with networking works, then why doesn't a clean boot? Msconfig, disable all non-microsoft services on the services tab, reboot and test a download. If ok... Then enable half of the services, reboot and test a download to eliminate\discover the culprit. Are there any critical or error events in the Event Viewer? Check there. Check hardware with a memory test and get the hard drive utility from the manufacturer and run a quick test. Downloads are stored in a temp file and then written to the drive for security. So, hardware could be an issue. Live internet is no problem (per your post)

I have also seen this behavior with DSL when there are bad lines, filters or connections. Check the hardware and wiring to the misbehaving machine.

I have two computers, both of them running Windows 7. One of them has been experiencing an odd problem for about six months now, and now that school is out I have time to mess with it. When I try to do certain things, the download speed periodically drops to zero. Literally, zero. Not just slow, but no bytes at all are being downloaded. Specifically, I've noticed it when using Firefox and Steam, (For the sake of science, I tried a few other browsers and got the same thing). I know I'm not *losing* connectivity, because everything that isn't downloading a file works fine. Skype calls work fine, Utorrent streams at a steady rate, but for some reason downloads have speed graphs that look like a heart rate monitor. It starts off strong, a nice solid 1 MB per second, and then after 10-30 seconds it'll slowly decline to 0, and sit there for anywhere from 10 seconds to half an hour before picking up to full speed again. THINGS I TRIED THAT HELPED: Safe Mode with Networking Engaged. Downloads proceed smooth and normal here, and do not randomly stop for hours on end the way they do in normal mode. That's how I've been doing things for the past few weeks; anything larger than 20 MB or so needs to be downloaded in safe mode, because the odds are against a download lasting the long without just stopping. THINGS I HAVE TRIED TO NO AVAIL: New Wires Firewalls off Antivirus scans Antiviruses off Disabling all programs on startup Getting rid of all processes and services that safe mode doesn't like Buying a new networking card Installing new networking drivers Uninstalling network drivers to force it into window's basic drivers making a new user profile and logging into that made sure it wasn't a power-saver setting resetting winsock catalog resetting TC/IP

I have also seen this behavior with DSL when there are bad lines, filters or connections. Check the hardware and wiring to the misbehaving machine. have tried new wires, different routers. No avail. I have no idea how to operate the event viewer or what could be useful. Currently the only non-microsoft services running are Steam and Hamachi. I'll try disabling them, but I doubt the problem is Steam since I've already tried uninstalling and reinstalling. EDIT: Nope. No luck so far. How do I do anything with the event viewer? I'm guessing there is a way I can extract meaningful files and send them to you and you can say "Ah! Your splitzer is debriefing."

I am sorry, I'll be more specific. I was referring to the pole to building wire and the building connection point to the connector wiring. Regarding the events, well, there should not be critical and only sporadic error events, Just read them and see if there is a clue. Hamachi seems to create issues. Look at these forum search results. http://social.technet.microsoft.com/Search/en-US/windows?query=Hamachi&rq=meta:Search.MSForums.GroupID(6acaa43a-f435-41fb-b68a-b44ccab4c2f4)+site:microsoft.com&rn=All+Windows+7+IT+Pro+Forums I'm quite confident that the building wires are functioning normally, since other computers hooked to the same router function normally. I've tried turning off hamachi; this does not resolve issue. I don't see anything in the event viewer that looks network related.

Maybe it's due to faulty winsock catalog problem, if you have run out of ideas, you might try to reset winsock catalog and see how it goes.

No luck. Next guess?

I'm sure its not a router settings issue, since I've got multiple computers running win7, and the issue cropped up during the winter, when I was at college. I built the computer at home in the summer and it worked fine for quite some time. No one has fiddled with router settings, so nothing there would've changed.

I am sorry, I'll be more specific. I was referring to the pole to building wire and the building connection point to the connector wiring. Regarding the events, well, there should not be critical and only sporadic error events, Just read them and see if there is a clue. Hamachi seems to create issues. Look at these forum search results. http://social.technet.microsoft.com/Search/en-US/windows?query=Hamachi&rq=meta:Search.MSForums.GroupID(6acaa43a-f435-41fb-b68a-b44ccab4c2f4)+site:microsoft.com&rn=All+Windows+7+IT+Pro+Forums