The biggest difference is that the 945 has 6MB of L3 cache, while the 840 has no L3 cache. With the two games you listed, there would be little, if any, difference. But, once you get in to more intense and labor intensive games or tasks, the L3 cache becomes a factor.
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The biggest difference is that the 945 has 6MB of L3 cache, while the 840 has no L3 cache. With the two games you listed, there would be little, if any, difference. But, once you get in to more intense and labor intensive games or tasks, the L3 cache becomes a factor.