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I'm planning on buying used RAM which was supposedly only used for a very short time. However, I'm afraid the seller might underestimate. Is there any way I can confirm the time for which the RAM modules were used?

I understand that the manufacturing date of the modules in question is a natural lower border, but this would be too inaccurate. Something like a counter for reads/writes, for power cycles or uptime would be sufficient.

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    As a side note, can anyone estimate how many read and/or write accesses a typical RAM module "suffers" during ist life time? – Hagen von Eitzen Oct 12 '14 at 15:41
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No, RAM doesn't retain anything when the power is removed from a module.

While it may be possible to add this functionality using a small flash RAM chip over and above the "normal" RAM, it would add to the cost and complexity. Futhermore, flash RAM has a limited number of writes, which means that the Flash RAM will probably reach the write limit way before the RAM fails, thus defeating the whole purpose of a "counter" mechanism.

If the power applied to a RAM module is always good, there is no reason why it cannot continue to work for a very long time.

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    "RAM doesn't retain anything when the power is removed" is going a bit far, there is actually already a small EEPROM holding SPD (and optionally XMP) data. It's true, however, that this does not hold the requested kind of data (it does however hold things like the manufacturer and production date in addition to the really necessary things like memory timings), and this is never erased/rewritten during normal operation. – Håkan Lindqvist Oct 12 '14 at 13:15
  • @HåkanLindqvist That is what I was getting at. The BIOS can read the correct timing settings for any RAM module from the module itself without the need of manual input (as was the case when I was younger). But since you suggest the required data are not present in there, it seems I'm mostly out of luck. Similarly, Lifeboy gave a good explanation of why my initial idea of an access counter was stupid. – mafu Oct 12 '14 at 15:04
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What Lifeboy wrote - no RAM modules are equipped with anything like SMART, like a hard drive, so you cannot have a report of power up time or read/write cycle count... (cycle counts would be pointless as well, as there would have to be billions of entries, as not all "bits" are read/written evenly - some bits might be overused, and others may never be used).

In a trade such as yours, it's Caveat Emptor. There are hardware tools which can inspect the individual bits and generate a profile/report, but you are likely never to see one outside an electronics lab. I would suggest investing in new hardware with a warranty. RAM is not terribly expensive these days.

  • Hi Darrin, and welcome to Server Fault and Stack Exchange. I would recommend being specific about which answer you are referring to, as there is very little in terms of fixed "above" and "below" on Stack Exchange; answer order can change based on user preferences, community voting, OP acceptance, and more. – user Oct 13 '14 at 8:54

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