Earlier quoted context omitted.
I dont even get this trend, wouldnt OpenAI be buying ECC RAM only anyway? Who in their right mind runs this much infrastructure on NON ECC RAM??? Makes no sense to me. Same with GPUs they aren't buying your 5090s. Peoples perception is wild to me.
At the chip level there’s no difference as far as I’m aware, you just have 9 bits per byte rather than 8 bits per byte physically on the module. More chips but not different chips.
For those who aren't well versed in the construction of memory modules: take a look at your DDR4 memory module, you'll see 8 identical chips per side if it's a non-ECC module, and 9 identical chips per side if it's an ECC module. That's because, for every byte, each bit is stored in a separate chip; the address and command buses are connected in parallel to all of them, while each chip gets a separate data line on the memory bus. For non-ECC memory modules, the data line which would be used for the parity/ECC bit is simply not connected, while on ECC memory modules, it's connected to the 9th chip.
(For DDR5, things are a bit different, since each memory module is split in two halves, with each half having 4 or 5 chips per side, but the principle is the same.)