便宜的HBM4，来了

Core Viewpoint - JEDEC is nearing the completion of the SPHBM4 standard, which aims to provide HBM4-level bandwidth with a narrower 512-bit interface, higher capacity, and lower integration costs through compatibility with traditional organic substrates. However, it is unlikely to replace GDDR memory [2][4]. Group 1: SPHBM4 Overview - SPHBM4 proposes to reduce the HBM4 memory interface width from 2048 bits to 512 bits while maintaining the same total bandwidth through a 4:1 serialization method [4]. - The design of SPHBM4 prioritizes performance and capacity over power consumption and cost, making it less suitable for gaming GPUs compared to GDDR7 [6]. Group 2: Cost and Integration Challenges - Although SPHBM4 is cheaper than HBM4 or HBM4E, it still requires stacked HBM DRAM chips, which are larger and more expensive than commodity DRAM ICs, leading to potential cost increases when replacing multiple GDDR7 chips with a single SPHBM4 chip [6]. - The integration of SPHBM4 on traditional organic substrates allows for 2.5D integration without expensive silicon interposers, potentially lowering costs and increasing design flexibility [8]. Group 3: Technical Considerations - SPHBM4 aims to achieve four times the memory capacity of HBM4 under the same chip conditions, but practical design often involves trade-offs between memory capacity, computational power, and chip functionality [5]. - The complexity of a 512-bit memory bus remains a challenge, but JEDEC's support for traditional organic substrates may alleviate some layout constraints in large packages [8].