Essentially, while games will very rarely press towards the edges of GPU technology in order to make sure they can run on a variety of systems, synthetic benchmarks can include multiple tests (like graphics tests 1 and 2 in Fire Strike) that can push towards very specific, and very different, edge cases and give you more information. And while some people may debate his assertion that benchmarks like 3DMark can help predict performance in real-world games in 24-36 months time, I am all about getting as much information as possible to our readers."
Slow computer got you down? Maybe a hardware upgrade should be in your cards, if so this guide to the Fundamentals of Upgrading a PC is an invaluable read. PCSTATS Tips