Saturday, May 23, 2026

Show HN: Running BitNet b1.58 inside DRAM by breaking DDR4 timing rules https://ift.tt/RX3q0HS

Show HN: Running BitNet b1.58 inside DRAM by breaking DDR4 timing rules I have been working on running BitNet b1.58 inside DRAM by intentionally breaking DDR4 timing rules. Also made a visual explainer: https://pcdeni.github.io/CaSA/explainer/ This is tested and works inside commercial off the shelf memory with custom memory controller in the FPGA. The underlying effect is well characterized in academic papers (cmu safari, simra, dram bender, etc). In the process of getting this to work I also made previously undocumented discovery about DDR behaviour: https://pcdeni.github.io/CaSA/explainer/xor-spread.html Overall it is a bit slow, since data (in full rows) needs to be moved even when what is actually needed is only the count of the '1' bits (popcount). To make it competitive memory die changes would be needed, but not as drastic as merging compute and memory into one silicon. This would then avoid the memory wall issue the industry is currently facing. May 24, 2026 at 12:24AM

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Show HN: Baby's First Cards – real photo flash cards for toddlers https://ift.tt/A1DK2pm

Show HN: Baby's First Cards – real photo flash cards for toddlers App maker here. I built this because most flash card apps use cartooni...