this is a long standing issue for me that has just gotten worse and I can't seem to find anyone online who has the same problem.
I have a brand new iMac from earlier in this year (around April). It had Mountain Lion, and is now upgraded to Mavericks. I had installed Windows 7 via Bootcamp, and it worked perfectly in pretty much every way.
But then I noticed that my wifi speeds were really slow. I have a 20/5Mbit connection and I was only getting 3/2 according to speedtest. However on all my other devices and on OSX I was still getting the full 20/5.
Restarting Windows or rebooting my router/modem setup (Airport Extreme) would usually fix it and give me full speeds until it would randomly come back the next time I booted up Windows. However recently it has become a permanent issue, with my bandwidth on Win 7 capped at 3Mb/s. I even restarted in Safe mode w/Networking and it still had the same speed limit. Sometimes it will start up at 10-11 Mb/s and then quickly drop down to 3.
The only change I can remember making is installing OSX Mavericks, but I don't see how that would effect the Windows side, and the issue existed intermittently prior to that.
I tried to install new Apple bootcamp drivers, but installing the NetworkAdapter one didn't seem to have any effect. I still need to try reinstalling all the drivers from Apple, but I get the feeling it won't do anything.
Microsoft refuses to help me since it is installed on a Mac. What can I do to figure out where the problem is? Do I have any better solution than a clean install?
Steps taken: Reboot every device involved. Reinstall network adapter driver. Restart in safe mode w/networking. Completely reset wifi network from scratch with no custom settings. Still need to try: Directly connect router to iMac with Ethernet and test speed. Completely reinstall Apple bootcamp drivers.
Specs: Mac: iMac Early 2013, 27" fully upgraded, Mountain Lion and then Mavericks Windows: Windows 7 64bit Home Premium