quck laptop l2 cache question

jonnyb

what's better - small l2 cache (512) and big fsb 3200mhz

or big cache (1mb) and small fsb 800mhz ?

thanks in advance

esuhl

I think the FSB (front side bus) connects the CPU to the northbridge (memory controller), while the L2 cache is used by the CPU to buffer memory contents. So with a 512kB L2 cache + 3.2GHz FSB, half the number of data can be cached, but the cache can be replenished four times (3200/800) times as quickly.

So I'd guess that a program that uses the CPU continuously (maybe something like video encoding, image processing, mathematical computation, etc.) would run faster with a 3.2GHz FSB, since the L2 cache would soon be emptied and the FSB would be the limiting factor in transferring data to the CPU; but a program that intermittently used CPU cycles might perform better with the 1MB L2 cache.

ddoris

You won't have 3200fsb for a while.
You are getting confused - why don't you approach this in a simpler way and simply look up the 2 cpu in a benchmark list ?

Eg http://www.cpubenchmark.net/cpu_list.php - there are others .

Then you have another question - does l2 matter much/how important is l2 cache ? The answer depends on what the cpu is doing.

Hammyman

All other things being relatively equal, BIG CACHE. Biggest cache you can find. L2 cache has a large effect on performance.

No such thing as a 3.2GHz FSB.

esuhl

Hammyman wrote: »

No such thing as a 3.2GHz FSB.

I thought that sounded a bit odd!

Several years ago, I remember opting for an AMD64 CPU because of the way that that these chips had a memory controller built in, so they could reference RAM directly without being limited by the speed of the FSB (if I remember rightly). I think Intel might have integrated memory controllers on the chip since around the time that the Core 2 Duo chips came out...

jonnyb

http://www.cclonline.com/product-info.asp?product_id=57115&category_id=1050&manufacturer_id=0&tid=lx.ptq02.028

I understand what you all say about the fsb, and 3200mhz being unattainable, but the link above mentions a bus speed of that figure.

Am I misunderstanding it ?

Thanks for the link to cpu benchmark ddoris.