Q6600 Processor Vs. Q9400

I have read benchmark comparisons and found the Q9400 and even the Q9300 to be a better performing processor compared to the Q6600 processor, even with 2MB less L2 cache.

I am just wondering, how significant of a difference do you think the Q6600 processor and the Q9400 processor is in a server environment? Currently I have a Q6600 processor but am looking to upgrade my server, possibly to the Q9400 processor..will it be worth it? It's not that much more expensive..the only thing I am concerned about is the 2mb L2 cache loss.

My site is "kind-of" high traffic. We receive a lot of connections and visitors, and most-importantly my sites are run by PHP and MySQL databases.

Please help me choose the right processor. Currently I have 4GB DDR2-800mhz installed, which I will be upgrading to 8GB DDR2-800mhz, no matter what processor I choose to run.

I discovered that upgrading to 1ghz RAM is just not worth the extra money because the performance gain is very little and not noticeable.

Would anyone possibly know of a Intel Quad Core processor that has 8mb or more of L2 cache, 1333mhz FSB, and is comparable to the processors listed above and relatively the same in price?