Slashdot Mirror

← Back to Stories (view on slashdot.org)

Firms Get Away with Selling Untested DRAM

Posted by timothy on from the cheap-n-cheerful dept.

peppytech75 writes "Melanie Hollands in IT Manager's Journal reports that 'In recent months, some Asian DRAM memory manufacturers have been getting away with selling untested ("UTT") DRAMs. Disturbingly, the practice seems to be getting traction at the lower portion of the module business. This is being done mostly by Taiwanese DRAM makers, who are undercutting the tier-1 guys by selling untested and unmarked parts.' What's the solution here? Or is there an actual solution to what amounts to pirate companies issuing counterfeit parts?" (IT Manager's Journal, like Slashdot, is part of OSTG.)

13 of 344 comments (clear)

  1. If you're stuck with one of these... by Anonymous Coward · · Score: 5, Informative

    Here is the obligitory Memtest86 post. It's a great program, and chances are that you might already have a copy on your Linux install CD depending on the distro. There are even kernel patches that allow you to avoid the bad bits if they are isolated enough.

    1. Re:If you're stuck with one of these... by Anonymous Coward · · Score: 5, Informative

      Although Memtest86 is absolutely great for detecting memory errors, I perfer Memtest86+.

      It's a more updated version of Memtest86 (which was last updated in November!), from the x86-secret team. It'll do the same thing, just that it will identify all the new procs and chipsets better.

      http://www.memtest.org/

      PS: I find if the RAM has any errors, the Modulo-20 test will nail them. Methinks it's test number 11 in Memtest86+.

    2. Re:If you're stuck with one of these... by gravygraphics · · Score: 5, Informative

      Memtest86 finds really bad ram, not good ram. Without having knowledge of how each chip is internally arranged, access to the chip's test modes and the ability to control the temperature, there is no way to finish testing a modern DRAM in our lifetime.

      Just take for example, the internal layout. If you had a 512M chip and you didn't know which cells were adjacent, you would have to write a single bit and read from every other word. We are talking x cells * y reads (*2 for writes). If you read 8 I/O's in parallel (remember I am talking about a chip, not a module) than we have 512M cells * (512/8)*2 = 7.2*10^16 OR 72 megagiga operations. Assuming you can keep about 200MHz worth of useful read/writes (remember most addresses aren't in the same page)than we are talking something like 11 years... for a single test that doesn't cover refresh, voltage/temperature margining.

      Oh one more thing. Tou are really not sure if when you write a 1, the device stores it as a high charge or a low charge. Without knowing this, you will have to redo that same pattern a BUNCH of times.

      Memtest86 is like a pilot walkaround on a plane. It can spot obvious things, but I sure hope I'm not the first one to fire up that jet engine.

  2. unmarked and untested == pirated? by qwertphobia · · Score: 5, Insightful

    I don't follow this analogy...

    --
    Never ask for directions from a two-headed tourist! -Big Bird
    1. Re:unmarked and untested == pirated? by Anonymous Coward · · Score: 5, Funny

      It would make sense if it was DD ARRRRRRR RAM.

    2. Re:unmarked and untested == pirated? by yknott · · Score: 5, Informative

      If you RTFA, the author was saying that these unmarked and untested DRAM chips can later be marked as if they came from a Tier 1 manufacturer. These chips can then be sold for a premium, yet still less than the Tier 1 price. In that case unmarked and untested = pirated.

    3. Re:unmarked and untested == pirated? by akadruid · · Score: 5, Insightful

      Piracy = buzzword = whatever you want it to mean.

      My neighbour pirated my parking space. That guy pirated my seat on the train. All it means is 'they've got my toys, mummy'.

      In the UK, we have big posters at cinemas which declare 'Piracy funds Terrorism'. Which is beautiful, since its 100% true, and depends completely on people misunderstanding it.

      --
      "Those who cast the votes decide nothing; those who count the votes decide everything." (attrib. Joseph Stalin)
  3. Why do people buy cheap ram? by flibble-san · · Score: 5, Insightful

    These days I don't reccomend anyone to buy cheap no-name unbranded RAM. Of all the PC hardware problems I've had over the years, about 80% are down to bad faulty generic RAM. I know only use Crucial or Kingston. They check the RAM, I know the RAM I buy is going to be working. RAM is one of the most important parts of any computer system. Is it really worth saving the £3-£5 by getting cheap unbranded RAM? As the saying goes, you get what you paid for.

    --
    My other sig is crap too
  4. So what else is new? by Mad+Hamster · · Score: 5, Funny

    I've heard of a company in the northwestern US which has gotten away with selling untested operating systems for years.

    - Did I make first post?

    --
    Yandelvayasna grldenwi stravenka
  5. Nothing New. by necrodeep · · Score: 5, Insightful

    The old saying stands true here... You get what you pay for. If you are going to only pay pennies on the dollar for Memory. Well you should expect a high number of failures.

    If your system memory is mission critical, you probably are going to buy top-shelf rather than bargain-basement, aren't you?

  6. Simple Solution by mrRay720 · · Score: 5, Insightful

    Really, it's easy. If they're selling untested, unmarked parts and this is a problem, just don't buy untested, unmarked parts! Let the market sort itself out. If the market decides that the cost saving here isn't worth it, the demand for slightly cheaper untested parts will surely dry up, and the manufacturers will catch on and stop trying to sell them.

    If there are enough people out there though who DO want the cost saving brought on by buying untested crap - let them! Nobody says you have to buy cheap crap if it's on the shelf. You get what you pay for. You want good quality - pay good money. You want bad quality - pay peanuts.

    Basic Economics, really. And it's not as if the likes of Crucial, Corsair, Kingston etc. are doing it.

    Why is this even an issue? I think it's commonly accepted wisdom EVERYWHERE that going for the lowest bidder will give you cheap rubbish. Computer components are no different.

  7. Big Deal... by jeremy_faller · · Score: 5, Interesting

    The article states that the manufactorers are finding it cheaper to have customers test the RAM, and return it. This has been the case for a number of products for a number of years. Anyone remember Motorola pagers (the POCSAG and FLEX ones)? They sold millions without testing them. It was cheaper for MOT to sell them without testing them, and just accept a number of returns.

  8. Re:Also try Prime95 by gkitty · · Score: 5, Informative
    I agree that memtest86 is useful but not sufficient and that prime95 is much more throrough. Memtest confirms that patterns that have been set hold their state briefly, which is a good test against gross failures (and I have seen these).

    But Prime95 confirms that no bit anywhere in nearly the complete memory space ever spuriously changes. I have seen plenty of memory that passes metest86 that fails prime95.

    Based on my experience, Corsair will replace memory that fails prime95. Mushkin will NOT (despite a "lifetime" warranty); they basically told me that memory can't be expected to be 100% perfect all the time and that prime95 was too strenuous; if it passes memtest86 there will be no replacement. My other modules (from Geil, Samsung, and a few old no-name sticks) have always been perfect. IMO it's unconscionable to sell untested ram given how hard it is to return.