Viruses can severely slow down your computer. Run anti virus software and get rid of any viruses that are on your computer.

Delete files to make more room in the memory of your computer. Freeing up memory on your computer will improve the performance.

Installing more ram into your computer can allow you to open new windows and load pages faster.

If the crack is relatively small and will not let too much dust into the computer then it is not urgent that the case should be fixed. However any cracks in the case will allow dust into the computer, and if too much dust is allowed to build up, then there are many problems that can occur.

Every fan has different speeds it can run at. Generally the longer the computer is in use, or the more demanding things that are being done on the computer, the harder the fan must work. This is normal behavior for computer fans.

The motherboard of your computer is built with somewhat of a warning system. This warning system can sense certain problems with your computer and will beep in different frequencies and durations to let you know what the problem is. There are a variety of problems that can happen, each containing its own code of beeps. When this happens the problems are usually more severe and should be taken care of as soon as possible. The following URL will bring you to a web site to help identify what these beeps mean: https://www.pantz.org/hardware/bios/beep...