A team is comparing the memory subsystems of a data-centre GPU and a server CPU to understand why each suits different work. The GPU pairs its cores with high-bandwidth memory, while the CPU pairs its cores with large-capacity DDR DIMMs. Which trade-off does this difference most directly express?
- AThe GPU favours very high memory bandwidth to feed thousands of parallel cores, while the CPU favours large capacity and lower-latency access for general-purpose working sets. Correct
- BThe GPU favours large memory capacity per device, while the CPU favours higher bandwidth to keep its few cores saturated during serial work.
- CThe GPU favours non-volatile memory to retain model weights across power cycles, while the CPU favours volatile memory for transient computation.
- DThe GPU favours error-corrected memory exclusively, while the CPU favours uncorrected memory to reduce access latency on each request.
Why A is correct: Correct. HBM gives the GPU the wide memory bandwidth its many cores demand, whereas CPU DDR memory prioritises capacity and latency for diverse general-purpose workloads, reflecting the throughput-versus-latency split.
Why B is wrong: Tempting because it sounds like a clean inversion, but it reverses reality: GPUs lead on bandwidth and CPUs lead on capacity, so the roles described are swapped.
Why C is wrong: Tempting because persistence matters for model storage, but both HBM and DDR are volatile; persistence is not the distinction between GPU and CPU main memory.
Why D is wrong: Tempting because ECC is associated with GPUs in some contexts, but server CPUs also widely use ECC DDR, so error correction is not the defining trade-off here.