SpeedUpMyPC optimizes your system in more than one way. Depending on your current system optimization level, certain optimization features might have more impact than others.
The individual features can be accessed by clicking on the "Optimization" and "Cleanup" tabs.
From the Optimization tab you can launch the "Memory Recovery" console, that lets you claim back RAM for other applications, especially after using some memory-hungry application such as a graphics editor. You can click on either one of the buttons to "Free up RAM" or perform a "Deep RAM recovery".
The "CPU optimization" feature has an "Application Booster" button, that lets you configure different applications with different CPU priority. So let us say that you are running a DVD backup software and at the same time browsing the internet, you might want to give higher CPU-priority to the DVD utility so as your other running applications do not interfere and result in failed (ruined) DVD backups.
The "StartUp" section in the Optimization tab lets you easily disable unnecessary programs running in the auto-startup each time Windows boots, and thus boosting the startup time.
On the "CleanUp" tab, you can access a very powerful temporary/junk file removal tool, which apart from protecting your privacy by deleting internet history, cookies etc, it also releases valuable hard-disk space for other important applications. In order to fine-tune the default settings according to your needs, open SpeedUpMyPC and click on the "Clean Up" tab. On the left side you will see a menu with "File Clean Up" as the first entry.
Click on "File Clean Up" to get to the list of junk files SpeedUpMyPC will look for. Notice that these 5 different categories can be individually selected or unselected, so if let's say you do not want the scan to detect "Lost Clusters" you can un-tick this option from this panel so that SpeedUpMyPC ignores any such files found. Further to this you can even customize which type of files fall under each category. If you click on the word "Lost Clusters", you will see that by default, lost clusters include any files with the extension "*.chk". You can add/edit this list by including or removing entries. If you click the "Default" button, all your changes will be undone and the default settings loaded. Another important and powerful feature is that you can omit any directories from being included for any particular category. To do this click on the "Ignore" button on the lower right corner and you can add a list of folders to be omitted from that particular category.
The "Privacy Protector" section is also somewhat configurable in the sense that you can select which areas you want to clean, such as "internet history", "cookies" etc.. To access the Privacy Protector, click on the "Clean Up" tab and then on "Privacy Protector" on the left. Each of the 12 different categories can be switched on or off. When a category is on (ticked), files and settings falling under that category will be removed from your system.
Also note that any junk files deleted are placed in the recycle-bin. These can be restored back as long as the recycle bin is not emptied.
If you do not want SpeedUpMyPC to load automatically every time with Windows, this can be disabled from the "Settings" tab.