The importance of L2 cache is actually quite high when you think about
what you are trying to achieve with the purchase of a new machine.
Level 2 Cache is used for accepting data directly from the memory
(RAM) of the PC and having it ready for the CPU to use a lot quicker
than if the CPU had to wait for the RAM to deliver the data over the
system bus directly.
When the first Celeron CPUs were released they had NO level 2 cache
and it showed in their very poor performance. Processor intensive
applications suffered badly when there was no or very little L2 cache
on the CPU.
This website gives a good overview of level 2 cache
Level 2 cache is most important for processor intensive applications
such as distributed computing
http://boinc.bakerlab.org/rosetta (this is an example of a distributed
computing application that is highly processor intensive.)
Video editing, 3d studio max or sound conversions are also very
processor intensive applications.
The question I would ask myself is this. Will I be doing a lot of CPU
intensive work, if the answer is YES I would opt for the E6600. Can I
afford the E6600 CPU without feeling the pinch instead of buying the
E6400, if the answer is YES get the E6600 CPU.
As I stated in your previous question, it is ALWAYS advisable to get
the best system you can afford right now rather than buying something
that will suffice. In the long run you will probably end up needing to
upgrade sooner than if you had spent 200 more dollars initially to get
a faster and higher specified machine now.
I do not want you to start thinking that the E6400 CPU is a slow
processor, compared to just about every desktop CPU you may have used
before it will be absolutely lightening fast (unless you used Intel
Xeon or Itanium 2 chips). Do not think that I am saying that buying
the E6400 will make you kick yourself, it wont, just that you would be
wiser to buy the E6600 if you are thinking of doing much more
processor intensive work.
This article will show you what % increases you will find between the
2MB and the 4MB L2 cache under different situations and usage.
A small paragraph from their page
"The 4MB L2 cache can increase performance by as much as 10% in some
situations. Such a performance improvement is definitely tangible, and
as applications grow larger in their working data sets then the
advantage of a larger cache will only become more visible.
Unfortunately, you do pay a price premium for this added performance
and future proofing as the cheapest 4MB L2 part is the E6600 priced at
If you're the type to upgrade often, then the extra cache is not worth
it as you're not getting enough of a present day increase in
performance to justify the added cost. However, if this processor will
be the basis for your system for the next several years, we'd strongly
recommend picking a 4MB flavor of Core 2."
I believe though that if you follow these rules of thumb and things to
think about you should be ok.
1 Can you afford and justify the extra cost of the CPU?
2 What will you be doing with the PC? Office, solitare, email, web
browsing and other non CPU intensive applications - E6400.
Gaming, sound editing, picture editing, video encoding and other CPU
intensive applications - E6600 (you have a longer shelf life with this
3 Always get the best machine you can afford. PCs are out of date
almost as soon as they are purchased, it is better to spend 200
dollars extra now than it is to find the PC you saved money on at
first doesn't do the job you need it to 3 years later and you need to
get a new machine.
If you purchased the 7900GT and the E6600 CPU with at least 1 Gigabyte
of system memory I feel that the computer you will have there will be
amazing and should be able to handle any task you throw at it.
If you need any more information don't hesitate to ask.