Reddit GPU comparison reveals Mac Studio as overpriced for LLM workloads

A Reddit user compiled an extensive comparison of GPUs and dedicated AI machines (like the Mac Studio) for running large language models (LLMs) and other AI workloads. The analysis uses metrics such as FP16 TFLOPS, VRAM capacity, memory bandwidth, and cost efficiency ($/TFLOP and $/GB). The data shows that the Mac Studio, often recommended for AI beginners, is significantly overpriced compared to used enterprise GPUs like the NVIDIA V100 or AMD Instinct MI50. For example, a used Radeon Instinct MI50 32GB costs ~$535–560 and delivers 26.5 TFLOPS with 1000 GB/s bandwidth, while a Mac Studio with similar compute costs thousands more.

The post also highlights that the RTX 4060 Ti 16GB ($400) offers the best $/TFLOP ratio at $4.5, while the RTX PRO 6000 Blackwell series ($7,000+) gives high absolute performance but poor value. The author warns against overhyping single-stream token generation benchmarks; prefill speed (processing context) is critical for multimodal models and real productivity. They recommend used P100s ($200 for dual cards) as an underrated entry point, offering 32GB VRAM with 700 GB/s bandwidth – matching M3 Ultra compute for a fraction of the cost. The discussion also notes that Spark and Strix machines are better value than Mac Studio, and that RTX 5090 isn't listed but implied as overkill for many use cases.