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old_user17401

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Message 31633 - Posted: 7 Dec 2007, 14:17:31 UTC

My machine had 2GB of RAM. A week ago I removed 1GB to be able to add a new 2GB dimm. A few days later, I got periodic OS crashes etc, so I ran a program to thoroughly test the memory and lo and behold, yes the new dimm is faulty. The original 1GB dimm works fine.

So I\'m back to a stable, tested 2GB (2x1) configuration. But I was crunching two 80 year climate models during this unreliable period. The models have survived this experience, but is the data still of value? They\'re both at about 30%.
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DJStarfox

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Message 31634 - Posted: 7 Dec 2007, 15:01:07 UTC - in response to Message 31633.  

If you have a backup from before the RAM, it may be worth restoring because you have coupled models which take a very long time to finish. On the other hand, chances are good that any errors caused the models to rollback themselves. So, I\'d say let it run as is; the odds are things will work themselves out. And of course, get a replacement RAM stick.
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Message 31635 - Posted: 7 Dec 2007, 17:32:22 UTC

Edward, the graphs for both these models look fine. I\'d follow DJS\'s advice to restore a pre-problem backup if you have one, and if not just crunch on. If anyone else is crunching the same models, you could keep an eye on their graphs which ought to turn out very similar though not necessarily identical.
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Message 31636 - Posted: 7 Dec 2007, 19:33:26 UTC

Good luck with those models, Edward. It will be good to add them to your already considerable total of climate models - have you seen IanM\'s great model stats for team Scotland? If not, click this link ;-)
Visit the Scotland team
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Message 32171 - Posted: 13 Jan 2008, 21:31:46 UTC - in response to Message 31636.  

Thanks.

Just got another memory so-dimm, this time I soak tested it first and it looks good. The machine seems to be running reliably. Pity one dead bit out of 16 billion caused such chaos before! So now I\'m crunching with 3GB :)
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Message 32173 - Posted: 14 Jan 2008, 18:00:40 UTC

Great stuff, Happy New Year and happy crunching! I see that the earlier link I provided to IanM\'s model stats for team Scotland no longer works, so here\'s an updated link to the model stats ;-)
Visit the Scotland team
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