CPU L2 cache vs clock speed

I'm planning on upgrading the CPU in my laptop. I have two choices so far a 1.6Ghz core with 2048KB (2MB) of L2 cache or a 2.5Ghz core with only 512KB of L2 cache. Both cores are 400FSB. The main problem I'm having is it cant render high resolution video smoothly. I have yet to look into the Cache vs core speed issue yet. Hopefully some of you have some real world experience on the topic.

 

I would take the 2.5Ghz 512KB L2 Cache CPU

 

+1

as important as the cache mevmory is, the difference between 1.6 and 2.5 GHz is too much to overlook.
for what cache does.....
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