Differences in MBP processors?

The 2.4 Unibody has 3MB L2 Cache, while the 2.53/2.66 both have 6MB L2 Cache. You probably wont see a difference in real world speed when comparing the systems, unless you are seriously pushing it to its limits, (video rendering, encoding etc). I am in the process of picking either the 2.4 or 2.66 and for a $400 price increase (edu discount), I am seriously considering the 2.4 just because I wont see the increased benefits of the cache and the video card memory does not benefit much from what I have read. I would basically be paying $400 for 4gb of ram and a bigger HD...

 

I believe the cache does matter. People made a big deal when the amount dropped from 4 mb to 3 mb of cache. It affects performence more than you think. Then again as you said you have to be doing something powerful. Even watching a hd download can push the limit so that you notice the difference.

Apple charges $300 to upgrade from 2.66 to 2.93 so you have to figure that the jump from 2.4 to 2.66 (even though it's a smaller increase there is more cache) would cost around $300. This seems like a good deal when you consider you receive double the ram, double video ram(again it really doesn't make a difference) and more hd space just for $100.

 

Here is a great article comparing the 2.4 with the 2.53 benchmarks and all. The benchmarks cannot be fully trusted because the speed increase is also coming from the fact that the processor is overall faster.

http://www.anandtech.com/mac/showdoc.aspx?i=3246&p=12