Hello Echidnite,
Thank you for posting your question on Microsoft Community.
I would like to know some information about the issue so that we could help you better.
Have you made any hardware or software changes to your computer?
What is the make and model of your desktop?
I would suggest you to try following methods and check if it helps.
Method 1:
Use this Microsoft help article and check.
Why is my Internet connection so slow?http://windows.microsoft.com/en-in/windows/why-internet-connection-slow#why-internet-connection-slow=windows-7
If it does not help, then use article in method 2.
Method 2:Is Internet Explorer slow? 5 things to try
Important Notes:
The Reset Internet Explorer Settings feature might reset security settings or privacy settings that you added to the list of Trusted Sites. The Reset Internet Explorer Settings feature might also reset parental control settings. We recommend that you note these sites before you use the Reset Internet Explorer Settings feature. Resetting Internet Explorer isn't reversible, and all previous settings are lost after reset.
Any data files that are infected may only be cleaned by deleting the file entirely, which means there is a potential for data loss.
I hope this information helps.
Please do let us know if you need any further assistance.
Thank you