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Topic Title: What's is the problem with Phenom??
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Created On: 12/17/2007 05:09 PM
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 12/17/2007 05:09 PM
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Hello all, first my name is carlos i'm from Portugal and i'm writing here in the forum because in the web we can read lots of things about the phenom processors but i think the best place to ask some questions its here. ok i think ppl allready saw tests about the phenoms processors. my question is what is happning with this processors, they have architecture to give more perfomance that we can see in tests.
I hope ppl can explain me and other ppl that have the same question about it.
Thanks all

Edited: 12/17/2007 at 05:12 PM by caracol
 12/18/2007 11:34 AM
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I heard that it has something to do with the L3 cache, but that's all I know. Yup, here it is, from Wikipedia:

"Before Phenom's release, it was discovered that a bug in the L3 cache in AMD's quad-core processors can cause a system lockup in rare circumstances. Phenom is affected by this bug up to and including stepping B2. There exist software workarounds to prevent this problem from occurring, although the workarounds typically employed incur a considerable performance penalty. This penalty was not accounted for in early pre-release previews of Phenom, so the performance of early Phenoms delivered to customers is expected to be somewhat below the benchmarks in these previews. Updated CPUs with the bug fixed will be named Phenom 9550 and 9650, and are supposed to arrive "mid to late Q1 2008." "

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 12/18/2007 03:32 PM
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The problem is more of marketing than a real visible problem. There is an eror on one of the CPUs registries, but the probability of it occuring is very low and requires very specific circumstances.

Let's not forget intel q6600 even B3 revision had about 30 known issues that were later solved with G0 stepping. And I did not hear anyone complain about it.

AMD could of certainly played this one a 'blame the OS thing' and I have the outmost respect for them because they didn't, even if the problem is software bypassable.


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 12/19/2007 06:29 AM
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"...Considerable performance penalty..." nothing, that's sum Intel rep' writing lies about AMD again. I read from the Inquirer (almost impartial!) that it'll be about 5-10% performance hit IF that. You know they're gonna be good so start saving!

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 12/19/2007 08:14 AM
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well i dont care if they have less performance now i think amd will fix this bugs and kick some intel processors *****. i'm allready waiting for my 9700 and my hd3870
ty all
 12/19/2007 10:04 AM
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The problem with the Phenom is a TLB bug which has his effect on the L3 cache. Due this bug the L3 can not run at full speed (still 1GHz, future 2,6GHz). There is a BIOS TLB work-around availible that will decrease the preformance by 5% up to 10% over the entire core. The B3 stepping will have a other fix that will have a preformance decrease of 1% as the rumors say.

Overall the core speed of the Phenom can be from stock up to 3,2 GHz stable without the BIOS fix. AMD has told the coming Black Edition will be the B3 stepping and will be able to show the real power of the K10 (K8L) core. So there is nothing to worry about. Also rumors tells us that AMD is already producing the B3 stepping from the beginning of December.

Back to the bug: Well the effect of the bug itself is low, sometimes you can get a BSOD if the core is running at 100% for 14 hours. For a normal user this bug will not be visible, but for important users like servers this is a problem so they apply the fix. If you ask me i think the entire talk about this bug is overhyped by all.

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