ECC DDR5 vs Non-ECC DDR5: Non-ECC is fine for your RTX 4090 rig

Don’t pay extra for ECC DDR5 — for a single 4090 or a few, consumer non-ECC RAM works perfectly well for deep learning. ECC was designed to catch bit flips, but on a consumer GPU rig, the chance of a silent memory error crashing your training is basically zero since the GPU does its own VRAM error correction. ECC DDR5 costs more, runs slightly slower, and gives no real benefit for most ML workloads. Save the money for more VRAM or a faster SSD.