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0 pointsjohndough5y ago0 comments

I ran a memory test for two weeks straight on a consumer laptop with 8 GB RAM and could not get a single bit flip, so your mileage may vary.

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bitcharmer5y ago

How did you run those tests? From what I understand on the topic, for your results to be statistically significant you need at least hundreds of machines and very rigid testing methodology.

avian5y ago

As someone who also ran a similar test myself and haven't seen a bit flip, I'm also skeptical of the 96% figure.

I'm too lazy to run the exact numbers right now, but with "4 GB, 96% percent chance, three days" as the hypothesis, I think you'll find that an experimental result of "8 GB, 0% chance, 14 days" is highly statistically significant.

Edit: rough back of napkin estimate - you're not seeing an event in roughly 10x trials (2x number of bits and ~5x number of days). Given hypothesis is true your experimental result has a probability of (1-0.96)^10 = very very small. Conclusion: hypothesis is false.

bitcharmer5y ago

The 96% figure comes from Google and was obtained in a large scale experiment over many months. I've been in this business long enough to have witnessed adverse effects of cosmic rays an non-ECC memory multiple times myself. I don't think you're sample gets anywhere near statistical significance. Not mentioning testing methodology.

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bitcharmer5y ago

How did you run those tests? From what I understand on the topic, for your results to be statistically significant you need at least hundreds of machines and very rigid testing methodology.

avian5y ago

As someone who also ran a similar test myself and haven't seen a bit flip, I'm also skeptical of the 96% figure.

bitcharmer5y ago

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