picking a CPU for single threaded string algorithms

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Hi ppl,

I am building a system for testing string algorithms.
I'm not an expert for hardware so any suggestions at all
are welcome, here are some facts, conclusions and questions:

1. Algorithms to be tested resemble Lempel-Ziv (~Zip) algorithms.
2. Only integer operations performance is important
3. Algorithms are very memory intensive and frequently read from random
locations spread across many GBs of ram.
4. Algorithms are single threaded.

I think that memory bandwidth+latency and processor integer
operations performance and speed are most important, cache not so much.

Currently I'm considering Core i5 680 as and Core i7 950
(they're within the budget).

One comparison shows that i5 660 (slower than i680) is
better than Core i7 975 (faster than i7 950), for
all the archiving benchmarks.

The only thing that could be an advantage of i7 is greater memory
bandwidth (3 vs. 2 memory controllers), which could speed up thing
when jumping randomly over GBs of RAM and reading chunks into cache.

How much difference will it be is questionable,
but do you think more memory controllers could speedup ram access
for single threaded apps? Would optimal ram configuration for
2/3 mem. controllers mean 2/3 ram modules?
Do you think Xeon's would make some difference
concerning integer operations speed or mem. bandwidth?

Thanks a lot for any comments