You get a brand new laptop, but after only a few days it's already beginning to run very slow. There could be a few reasons why it would run slow and there is the possibility that you did nothing to cause it.
Not Enough Memory
If you bought a cheap laptop, once you install all your programs onto it, there may not be enough memory to run them all. Since the computer cannot handle all the data flowing through its circuits, it runs slow.
Even if you have a brand new computer and have installed antivirus software you could still have picked up a virus or spyware from the Internet. To get your computer running at peak performance again, you will have to get rid of the offending programs.
No matter how new your computer is, if you put too much on it, it is going to run slow. The more you download or install onto your hard drive, the slower it is going to run.