Bam, here's your MTU instructions. No guarantees that you problem is actually caused by improper MTU though.
In Command Prompt, enter this:
code:
ping -f -l 1472 www.dslreports.com
Raise the number until you get errors about fragmentation. The highest number that doesn't give fragmentation errors will be your magic number.
Hint: You'll probably end up finding either 1472 or 1464 as your magic number, so try those first, and then start checking every other number.
Your optimal MTU value will be your magic number plus 28.
Use
DrTCP to change your computers' MTU value to the optimal value that you have found. You might as well set it on your router as well. There is no proper place to change the settings, if you want to do it without using any extra programs, you'll be editing hex values directly in the registry.
The optimal value won't constantly change, so don't bother retesting it regularly. If you cahange your connection, then it may be worth retesting though.
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