Whats the processor cache?

I see some processors have 2mb, others 6mb. what difference does it make?

 

The processor cache is a small amount of memory that is built into the processor's die. This memory runs at the same clockspeed as the processor's core and is used as ultra-fast memory to store parts of running programs and such. The greater amount of this cache, generally the faster the processor will be. The greatest amount at the moment is 6MB and it can be found on the Intel Core 2 Duo T9xxx line of processors. The T8xxx (like my laptop) has only 3.

-J.B.

 

Thanks for the info.
Okay now I'm about to buy a laptop, and I got to choose between the 2mb, or 3mb, or 6mb.. how will I notice the difference between all three in real life? Like when using photoshop, surfing the net, running several programs in the background and so on.

thanks again

 

For more intensive tasks, the difference between cache can become very noticeable. If all you do is surf the web or occasionally write a word document, it won't make much difference.

 

2MB vs 4MB Max=10% avg=3.5 3MB vs 6MB Max=8% avg=3%





Keep in mind that the 3MB vs 6MB is pitting a 2.4Ghz against a 2.5Ghz that is why some adjustment must be to account for clocks. The 2MB vs 4MB is at the same clock. To compare 2MB to 3MB a little creative guessing must be applied. Same with 3MB vs 4MB, 4MB vs 6MB.

One thing to be aware of is, as you keep increasing L2 you get diminishing returns. I am not trying to say L2 size does not matter but if you had 128KB L2 vs 256KB the performance difference likely would be much greater than for example 3MB vs 6MB. Also as long as I have strolled at least on a superficial level into theory here are some things to keep in mind. You cannot compare L2 directly with different CPU designs.

With Intel not an issue as Intel keeps applying the same basic strategy and improving upon it including increasing L2. And while I am very aware C2D is the king in the mobile market. AMD applies a very different strategy. The only general comments I can make about this are. Remember when I said as cache keeps getting larger the returns are less, to be clear I am not saying larger cache ever has a detrimental affect just that the increase becomes smaller and smaller relative to the increase in size.

No one talks about L1 for some reason? AMD has twice the L1 vs Intel. L1 stores what are frequently referred to as instructions. AMD does not share their cache between cores Intel does. Which is better? At this point Intel is winning on performance but L2 and L1 are only one part of that equation.

In theory there are advantages to AMD's design but as of this point on notebooks have not been able to achieve superior performance over Intel. Servers are an entirely different animal that I am not going to jump into at this point but will say it does have to do with both design and function. AMD does better on those than with their mobile solutions. Here is a link to wiki on the L2 subject if you don't already have headache and an interest in learning what L2 is and what it does.

 

A quote from Intel themselves...

"Imagine arriving at the grocery store and having all your favorite food fly off the shelves and fill the cart in minutes.

That’s L2 cache. It remembers the information accessed most frequently in your computer so you can easily get to it without those annoying lags. (Just don’t expect it to remember documents you didn’t save. It’s just a computer, not your mother.)

Tip! More L2 cache reduces bottlenecks and helps speed memory performance."

Intel.

 

Intel says? Yea, not bad but not a very good explanation. Says nothing about how much you need?

 

Intel's bigger L2 cache is their answer for not having their memory controller built into their processors. It bridges the latency gap in operations that are memory intensive.

 

Doesn't say how much you need..but the OP didn't ask that...the OP asked what's the difference between the two. That should give the OP a very good understanding of the difference. Don't you think?

EDIT: The difference is..the more L2 cache the Better!

 

I heard AMDs dont even need that much L2 cache due to integrated memory controller?


doesnt that make AMD's little less dependant on L2 cache?

 

After Penryn Intel is moving to on board memory controller! The L2 will go down to 256KB per core! I could tell you more but it is late and well I don't want to. Taking some of AMD's Ideas? Intel fan boy's this is for you!

 

Wow..so intel stealing AMDs technology?

this is big news.

 

Ever heard of Nehalem? Desktop versions coming end of this year and laptops by next summer.

 

They're not stealing the idea, they're using what's best

 

My Intel fanboy detector just maxed out, over heated and caught fire?

Intel is going to a large L3. My brother has one of the 1st P4 extremes that has a large L3. I know I am overstating, AMD did not invent what Intel is shifting to but did implement the technology before Intel. I am excited about the new products coming out. They are so far beyond what 99% of us need! But that does not matter I still want!

 

Oh trust me, I never cared much for brands, I just want the cheapest and fastest option. Intel is just that at the moment...

 

I am in the same boat as eleron911. I've had both AMD and Intel. I've recommended both to my friends and families depending on their needs and budget.

As much as i don't wanna sound like i'm defending Intel for their move to incorporate the memory controller in their CPUs but I think it's a great move business wise. They've seen the benefits of integrated memory controller to further push the performance level of their CPUs, so why not adapt it? It's not stealing but following something that works. If they can compete and can implement the technology better than the competition, wouldn't that benefit us consumers for having a choice in the technology that we may prefer?

I'd say it's a good move if they can implement it right.

 

The Future is Intel!....Count me in as a Fan Boy powerpack...I think u know this already.

 

I say i have to belive that.

I have nothing against AMD. I almost bought one twice and ive used several AMD's before. But looking recently at which one has been more bought and preferred, it lies with intel. Also, Intels are generally cooler and have more Cashe. Now, that you said AMD has some kind of memory controller thing, maybe the cashe part is wrong.

 

You were already on the list. Now you have an asterisk by your name, "super" fanboy.

I also hope it works out, and if it does I would buy. I am going Intel on my next notebook soon unless this PUMA thing knocks my socks off.

 

Yes...i was looking forward to Montevina, but now i'm looking forward to Calpella!!! Main reason being because of the new technology it would have that elliminates the FSB.