There is 5% benefit in 3DMark Vantage’s CPU test, but the overall score and GPU test show hardly any benefit at all. Let’s look at some game titles.
Frame rates increase by 8% on Far Cry with medium settings if you exchange the entry-level Athlon II X4 quad-core to a Phenom II X4 at the same clock speed.
A 5.7% benefit on GTA IV isn’t much. The L3 cache has little impact here.
Left 4 Dead is different. The processor with L3 cache delivers almost 20% faster frame rates.