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Erratum Plagues Quad-Core Opterons, Phenoms

theraindog writes "Errata are not uncommon with new processors, but a problem with the TLB logic in AMD's quad-core Opteron and Phenom processors appears to be quite serious. The erratum is so severe that AMD has issued a 'stop ship' order on all quad-core Opterons. AMD has also blamed this bug for the delay of the 2.4GHz Phenom, despite the fact that the erratum is unrelated to clock speed. A BIOS-based workaround for the issue has been made available to motherboard makers, but it apparently carries a 10-20% performance penalty. What's more disturbing is that AMD knew of the erratum and the potential performance hit associated with fixing it before it launched the Phenom processor. Hardware provided to the press for reviews did not include the fix, conveniently overstating Phenom performance."

12 of 226 comments (clear)

  1. Bummer by El+Pollo+Loco · · Score: 3, Insightful

    Wow, bad times for AMD. They're losing the war against intel, and now have another set back. A 20% performance penalty is simply unacceptable for any processor. The fact that it is for brand new ones makes it an even bigger slap in the face for consumers.

  2. Re:What??? by fitten · · Score: 4, Insightful

    Every CPU maker publishes the errata for their CPUs because system designers/vendors/whatever need to know these things. Every CPU made for the past (insert very long time in the computer world here) has had a big list of errata publicly published. Just got to the Intel or AMD site, for example, and look up the errata on the PPro, P3, P4, Core, Core2, Athlon, Athlon XP, Athlon64, Athlon64 X2, or whatever your favorite CPU happens to be.

    The thing is, the CPU is actually broken a bit and AMD has pulled the Barcelona line but are continuing to sell the Phenom(inal Failure) line to customers and, evidently, don't plan to 'fix' the problem later (Intel offered replacements for the Pentium floating point bug after they got dinged on it, for example... I know... I had one and replaced it).

    So... if you actually get your hands on (or got your hands on) a Phenom, realize you have a broken CPU and the more you load it, the more likely you'll have stability issues.... and AMD isn't (currently) going to fix it.

  3. Re:NDA for patch? by wizardforce · · Score: 2, Insightful

    I also wonder: Red Hat, why?
    I imagine that their reasoning was that it was better to offer a patch, closed or not that benefited their users that would choose to make use of this processor. The solution isn't elegant, more like repairing an aircraft's hull with duct tape but apparently it is better than the alternatives they tried.
    --
    Sigs are too short to say anything truly profound so read the above post instead.
  4. "because", not "despite" by statemachine · · Score: 5, Insightful

    AMD has also blamed this bug for the delay of the 2.4GHz Phenom, despite the fact that the erratum is unrelated to clock speed. [Emphasis added.]

    Why does the summary claim this? I read through both articles, and AMD says this is a hardware issue across both chip models. Since this is a hardware issue, wouldn't it stand to reason that AMD would hold up a related chip because it's a hardware bug across both chip models and not because it's a clock speed issue? I'm not sure where the "despite" comes into play. I didn't see where the article said that AMD is not delaying a different speed Phenom.

  5. No, but it looks bad by _merlin · · Score: 5, Insightful

    It's not like there aren't problems with Intel's CPUs - just take a look at the problems with the MMU in the Core 2 - but no-one is suggesting Intel is doomed. It would just be better if AMD had admitted this when they first knew about the issue rather than sending out review units that are known to have serious issues.

    1. Re:No, but it looks bad by ceoyoyo · · Score: 4, Insightful

      No, but AMD seems to be in a pretty delicate state. Their stock is pretty low and they've taken a beating from a newly-competitive Intel. They don't have a big advantage in processor speed anymore, nor power, nor even price. Halting shipment on an entire line? Not good. If they eventually have to recall it... bad.

      It might not be AMD's doom, but they're really not that many big screwups away.

  6. Re:NDA for patch? by Crispy+Critters · · Score: 4, Insightful
    It is silly to think that RH is ignoring the GPL.

    There are other possibilities that are more likely. For example, perhaps the patched kernel is doing something like loading microcode into the processor. The kernel code would be GPLed but the microcode would not be.

  7. Depends ... by Pinky's+Brain · · Score: 2, Insightful

    As long as the diff doesn't contain any of the original code and the patch is distributed in isolation then there is no conflict with the GPL ... if RH distributes a binary kernel though then they are in violation of the GPL, this would make RH liable but I don't know whether your rights under the GPL or the prohibitions under the NDA take precedence for the recipient though.

  8. Re:Old issue, really by merreborn · · Score: 2, Insightful

    AMD would be fine if they had an expensive chip they could sell at a premium, or a very cheap to produce chip they could sell for the budget crowd, but right now they have Acura production costs coupled with Kia per-unit revenues: bad times.


    AMD actually still rules the absolute low end of the market (and has for years). Semprons ($30+) and old X2s ($60+, new retail box) are dirt cheap, and it's simply not possible to get better performance per dollar.

    There isn't much a $60 X2 can't do in your average desktop.
  9. Re:This doesn't have to be so bad by canuck57 · · Score: 2, Insightful

    AMD can turn this into a PR boon to one-up Intel at the "Green" initiatives. All they have to do is repurpose the uncut wafers of these chips as solar panels and then retile the outside of all their buildings with the panels. This will save money on their energy bills and they can even start a new Ad Campaign:

    It will not stop me from buying AMD. The only processor I have ever (of 20+) had that cooked was a P4 2.4GHz HT on a Intel PERL mobo no less! But I have abused two older AMD chips I still have running with over-clocking, dust plugs in the fans etc and in a an el-cheap mobos. One even ran with a defective fan for months. It did crash, but I caught the fan doing it one day where it would just stall. Replaced the fan, been running ever since. Those AMD just keeps on ticking, a 1200 and 2000+. Totally abused and owe me nothing.

    And the AMD X2 I bought last year, runs flawlessly. BTW, I do have 2 P4 heaters still running. Yep, I have a few, even a Sparc.

    But looking for another X2 for Christmas. And anyone who buys a chip with a serial number increment of less than 100,000 for production or stability are nuts. Just like a Chrysler, GM or Ford, you don't want the first 100,000, nor the last 100,000. The sweet spot is in the middle.

    And although down, I do look forward to the day AMD kicks Intel ass once again. Too bad AMD execs sidelined AMD engineering with this ATI noose. ATI is going to set AMD back 4 years by the time all is counted. I do have respect for Intel PIII 650Mhz duals in a Supermicro though, they too keep ticking.

  10. Why AMD Released Faulty CPUs: Possible Theory by Ma3oxuct · · Score: 3, Insightful
    If you look at AMD's financial statements (http://sec.gov/Archives/edgar/data/2488/000119312507238299/d10q.htm#tx48043_5) for the last quarter, it has been loosing a lot of cash. This leads me to believe that they released faulty CPUs, right before the holidays, in order to get some cash in the short term.

    The idea was to gain some cash to sustain operations until a faultless (i.e. no major faults) CPU can be released. Those that bought faulty CPUs will get their CPUs replaced as soon as faultless CPUs are completed. In some sense you can look at AMD's action as taking out a long term loan.

    A counter argument to my theory can be that AMD would not risk its reputation to take out a "cash loan" in such a manner. However, the risk of losing reputation is justified if we consider another major factor at play: the holidays. It is less likely that AMD would gain the same (or even close to the same) cash flows if they would have released the CPUs after the holidays.

    AMD now has some cash and is able to breath a little bit. When it releases fixed CPUs it will be able to continue where it left off.

  11. Oh please knock it off by Sycraft-fu · · Score: 2, Insightful

    The whole "Intel is t3h hot!!!" thing has gotten old. Yes, P4s were very inefficient chips. Not so with their modern lineup. Core processors are quite efficient power wise for their given level of performance. They also scale way down, there are Core Solos with only a 3 watt TDP spec. Shouting about the Core lineup using a lot of power when it is AMD's processors that you use as the alternative makes little sense.

    It is just silly to dredge up old crap and keep using it. It actually weakens any point you try to make because it makes you look as though you don't know what you are talking about. Name calling is bad enough but when it is outdated name calling it is really silly.

    By the way, I wouldn't crow too much about price either. I can't find many Phenoms available but the 2.2GHz one Newegg sells is $245. A 2.4GHz Core 2 Quad is $260. Even assuming the Phenom is faster (which would be real questionable especially in light of the patch) that makes it 94% of the price, not 60%. Not a significant cost savings.