L2 cache for Opteron or X2 chips

[janderia]

I'm shopping for an Opteron (or x2 maybe) and was wondering about the differences in L2 cache options. Is there a performance gain in having the L2 cache at 2MB as opposed to 2x1MB? I don't understand the difference here as it looks like both are 2MB in the end.

Basically, I'm looking in the budget range of $400 or less for the cpu.

Thanks!

 

[mdd1963]

" in having the L2 cache at 2MB as opposed to 2x1MB? I don't understand the difference here as it looks like both are 2MB in the end."

For all Opterons, each core has it's own 1 Mb cache, so some advertisers will add them, for a total of 2 meg...

THe 4400 (2.2G) and 4800 (2.4G) each have 1 meg of L2 cache per core as well...

 

[janderia]

The Opteron 170 Denmark dual-core advertised here is listed as just 2MB cache (rather than 1x2MB:

http://www.newegg.com/Product/Product.asp?Item=N82E16819103586#DetailSpecs

I'm getting this from Newegg's site. Your explanation makes perfect sense but the fact that New Egg will list this dual-core as 2MB and other dual-cores as 2X1MB confuses me. This would lead me to believe that the vendor just isn't consistant in how they list the cache.

 

[linux_0]

Yes the total L2 cache is 2MB however it is normally referred to as 2x1MB because each core has it's own integrated full speed L2 cache i.e. the cache is not shared, it is dedicated to each core.

IIRC the 2 cores have a dedicated HT bus they can use to communicate with each other at 1000MHz Full Duplex or effectively 2000MHz.

 

[RichPLS]

Either way is legit as far as I am concerned, 2x1MB cache or 2MB cache, as long as they do not state 2x2MB cache.
Either way it is better than 2x512k cache, or 1MB cache total...
If the details concern one much, surely they will also look up other misc. specs to get to the bottom of the issues, which can only properly be done by going to the manufacturers site and getting the scoop direct, not 3rd party info...