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Comment by dmoy | Hacker News Reader

Yes, but it costs more (in $$ and performance)

Is there still a whacking great price premium between ECC and non-ECC memory for desktop, but not server, motherboards? If so then that suggests that there's more going on here than a simple expression of consumer choice.

>Is there still a whacking great price premium between ECC and non-ECC memory for desktop, but not server, motherboards?

Yes for both.

Price: On pcpartpicker a stick of 16GB DDR4-3200 memory without ECC costs $28.99[2], but the ECC version costs $52.99[1]. Even factoring in that ECC ram comes with an extra chip, it's still 62% more.

Performance: using the same links above, we see that ECC ram tops out at 3200 MT/s, whereas for non-ECC you can get 4000+ MT/s. The brand selection is also better, which is critical if you want to get high performance memory chips like samsung b-die or micron E die.

[1] https://pcpartpicker.com/products/memory/#b=ddr4&E=1&sort=pr...

[2] https://pcpartpicker.com/products/memory/#b=ddr4&E=0&sort=pr...

> Performance: using the same links above, we see that ECC ram tops out at 3200 MT/s, whereas for non-ECC you can get 4000+ MT/s. The brand selection is also better, which is critical if you want to get high performance memory chips like samsung b-die or micron E die.

Notable is that the max speed of 3200 MT/s for ECC is due to that being the fastest JEDEC standard for DDR4, you're not getting the XMP-profiles to run them faster and will have to resort to manual overclocking.

I was thinking about doing error correction in software at driver/kernel level as opposed to using ECC RAM.

Even though ECC contains the logic of doing error correction in one chip, that doesn't justify double prices.

> about doing error correction in software at driver/kernel level as opposed

I have no clue how that works without significant performance cost

As a sibling said, rhis would certainly come at a huge performance cost. Inline/Inband ECC is showing up again recently, which might be of interest. It comes at a performance cost too, but basically you use regular RAM, and the memory controller issues extra read/writes for the ECC data separately from the rest of the data for a given address.

If that gains traction, it could bring ECC to the masses.

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