Celeron-M Cache Issue

[viv5]

This is an excerpt from an article on Celeron-M vs Pentium-M.

It's true that the Celeron M is based on the Banias core, like its big brother the Pentium M. However, only 512 kB of the 1MB L2 cache on the Celeron M die are addressable. The remaining 50% of the cache is deactivated during the CPU's validation process. With regard to the size of the die, there is no difference between the two processors, since the space taken by the cache is identical.

Now does that mean that only 512Kb of L2 Cache in Celeron-M (out of 1MB) is useful?

 

[mavalpha]

a) That's outdated. Dothan has 2MB instead of 1MB, and the Celeron based on it has 1MB instead of 512KB.
b) Yes, that means that half of the cache on the die is disabled, and only the other half is accessible. A different story is that this is still plenty, as Tom's Hardware found a year ago on Banias that comparable speed Pentium-M and Celeron-M processors perform within 1% of one another.

 

[Pongi]

As mavalpha said, that information is a bit outdated as it applies to the Banias based Celeron M.

Still, 512KB L2 cache is pretty damn good for a Celeron. I have a Banias Celeron M 310 (1.2Ghz) that plays Doom 3 just fine on my desktop.

 

[viv5]

As mavalpha said, that information is a bit outdated as it applies to the Banias based Celeron M.

So on what architecture is Celeron M 1.4 360 processor based on?

And what is it's actual L2 Cache (1MB as publicized by Intel or just 512KB)?

 

[lithium726]

1mb.

if intel advertises 1mb, it has 1mb. the pentium m counterpart as 2mb.

 

[viv5]

1mb.

if intel advertises 1mb, it has 1mb. the pentium m counterpart as 2mb.

And what about the core: is it banias or dothan?

 

[mavalpha]

Dothan. All processors with numbers instead of raw gigahertz are either Dothan or Prescott, depending on whether they are desktop or mobile chips.

 

[viv5]

Dothan. All processors with numbers instead of raw gigahertz are either Dothan or Prescott, depending on whether they are desktop or mobile chips.

But here Ghz are also mentioned.
Celeron-M 1.4GHz 360

 

[viv5]

Intel's website has no information regarding its(Celeron-M 1.4Ghz 360) core.
Cache memory mentioned is 1MB L2 cache.

Now considering the text in the article 'Celeron-M vs Pentium-M'

However, only 512 kB of the 1MB L2 cache on the Celeron M die are addressable. The remaining 50% of the cache is deactivated during the CPU's validation process.

I am made to believe that the actual cache that's there in Celeron-M 1.4Ghz 360, is half of what has been mentioned in the specifications.


Now is it 1MB?
or
Do I believe that the other 512Kb is not addressable and hence the actual memory is 512Kb?

I am confused.

Please suggest.
Thanks.

 

[lithium726]

And what about the core: is it banias or dothan?

its a dothan. it shouldnt matter, intel always advertised 512kb on banias celerons, not 1mb like on the dothan.

But here Ghz are also mentioned.
Celeron-M 1.4GHz 360

so? Banias core chips never even had processor numbers. just cuase theyre telling what frequency its running at means nothing.

Intel's website has no information regarding its(Celeron-M 1.4Ghz 360) core.
Cache memory mentioned is 1MB L2 cache.

heres the 360: http://processorfinder.intel.com/scripts/details.asp?sSpec=SL7LS&ProcFam=67&PkgType=ALL&SysBusSpd=ALL&CorSpd=ALL
and heres all celeron-M's: http://processorfinder.intel.com/scripts/list.asp?ProcFam=67&NoNav=NO&CorSpd=ALL&SysBusSpd=ALL&MfgTech=ALL&step=ALL&cache=ALL&Pkgtype=ALL&btnFOS=Filter+on+selections

if Intel specs these chips at 1MB, theyre one mb. there is nothing else to understand here. the original banias core c-ms had 512kb disabled. the dothan core c-m has 1mb disabled. every celeron since celerons were introduced has had cache disabled, and the first celerons didnt have cache to begin with. AMD's semperons and old durons had cache disabled. AMD and Intel always advertise what the chips actually have, not what they have on die, reguardless of whether its enabled or not.

youll notice that some chips are listed as 512kb. if you go into their respective webpages, youll notice "process: 130nm"(or .13 micron). those are banias. 90nm is dothan

Now considering the text in the article 'Celeron-M vs Pentium-M'

I am made to believe that the actual cache that's there in Celeron-M 1.4Ghz 360, is half of what has been mentioned in the specifications.

we've already told you that article is outdated. why the hell would intel sell a chip to an end user with half of what they said? that would piss consumers off greatly.

I am confused.

no reason to still be confused. we've all been telling you it actually has 1mb this whole thread, its not like we're blowing hot air up your skirt or something...

 

[mavalpha]

Take it easy on him... remember that not everyone reads as much technical stuff as we do. We, the "knowledgeable ones," are here to make the novices' lives easier- not harder. Not to be an ass, I'm just short on sleep right now so I couldn't think how to phrase is gently.

OP:
See what lithium726 said, and consider it repeated. I agree with him 100%, except for the filler.

 

[lithium726]

Take it easy on him... remember that not everyone reads as much technical stuff as we do. We, the "knowledgeable ones," are here to make the novices' lives easier- not harder. Not to be an ass, I'm just short on sleep right now so I couldn't think how to phrase is gently.

OP:
See what lithium726 said, and consider it repeated. I agree with him 100%, except for the filler.

i know i was being horribly blunt and too hte point, i was feeling like an ass this morning too

sorry if i came off a little harsh.

 

[viv5]

It’s okay lithium.

You are like our teachers, big brothers.
I really appreciate your efforts.


Thanks lithium and mavalpha for your support and for clearing my doubts.

I hope I will not make these sort of silly mistakes in future.


Cheers.
Viv