"1. Getting to the Settings Menu. Bring your mouse pointer to the right side of the screen to get to the Settings menu, which Windows represents with a large icon of a gear. From this menu, select the "PC Info" to bring up the System utility.
2. Checking Out Your System. The System window will present you with a Windows Experience Index for your computer, which is a pretty useless number, to be honest; it's calculated based on your available Random Access Memory (RAM), your processor, your video card and your hard disk transfer rate, but it's not the best number to use if you're trying to figure out whether or not your computer can run a particular program.
This screen will also show you your processor type and installed RAM, which are far more useful metrics. If you're trying to determine whether you can run a game or another graphics-heavy application, you'll want to click over to the Device Manager to check out your video card."
If you are using Windows 8, this is how you check what kind of graphics card you have. Any other Windows edition will have a similar process. If you are on a Mac, click on the apple in the top-right corner and then "About This Mac". What we are trying to determine is whether you have an integrated graphics card or a dedicated one. Any CPU you purchase now will have an integrated graphics card built in. It is strong enough for average things like internet browsing, but not quite enough for gaming. A dedicated graphics card is one that is put into your PC as a separate entity. It is not part of the processor. These are generally made for people who need something a little more and are vary from about equivalent to the power of a integrated graphics card to many times its strength. Because you do not know what you have, chances are its either an integrated or a less powerful dedicated. In either case, it might be able to pull of low settings on Ghosts, but at that point, it is dependent on your resolution.