Knowing your system information would help.
You can access to those via:
Method 2) If you are using Windows, you can right click 'My Computer', then select 'Properties', then the 'system# tab tells you information about your system.
Method 3) If you are using Windows, you can run dxdiag by either: (XP) Start -> Run
: 'dxdiag', run dxdiag. or (Vista/7): Start -> Search bar: dxdiag, run dxdiag.
Tell us what is your videocard/Gpu and rest should be easy enough. :P