Mac Studio M3 Ultra 512 GB vs RTX PRO 6000 for local AI
Today the RTX PRO 6000 is cheaper: $16,499 against $18,566.48 for the Mac Studio M3 Ultra 512 GB. Per gigabyte of memory the Mac Studio M3 Ultra 512 GB wins, $36 against $171. For Qwen3.8 27B · Q4_K_M the RTX PRO 6000 is faster, about 71 against 30 tokens per second. The Mac Studio M3 Ultra 512 GB holds more, 512 GB against 96 GB, and fits 27 of our 28 reference models at Q4_K_M where the RTX PRO 6000 fits 18.
| Apple Mac Studio M3 Ultra, 512 GB | NVIDIA RTX PRO 6000 Blackwell | |
|---|---|---|
| Lowest price today, delivered | $18,566.48 on eBay | $16,499 on eBay |
| Price per GB | $36/GB | $171/GB |
| Memory | 512 GB LPDDR5 unified | 96 GB GDDR7 ECC |
| Memory bandwidth | 819 GB/s | 1,792 GB/s |
| FP16 compute, dense | 28.4 TFLOPS | 504 TFLOPS |
| Reference models that fit at Q4_K_M | 27 of 28 | 18 of 28 |
| Power | n/a | 600 W |
| Form factor | Desktop box, 197 x 197 x 95 mm | Dual slot, full height (Workstation Edition) |
| Interface | unified memory | PCIe 5 |
| Software platform | metal | cuda |
| Launched | 2025 | 2025 |
| Launch price | $9,499 | $8,565 |
Qwen3.8 27B · Q4_K_M by quantization
| Quant | Mac Studio M3 Ultra 512 GB | RTX PRO 6000 |
|---|---|---|
| FP16 | ~9.1 tok/s | ~22 tok/s |
| Q8_0 | ~17 tok/s | ~41 tok/s |
| Q6_K | ~22 tok/s | ~53 tok/s |
| Q5_K_M | ~26 tok/s | ~61 tok/s |
| Q4_K_M | ~30 tok/s | ~71 tok/s |
| Q3_K_M | ~37 tok/s | ~88 tok/s |
| IQ2_M | ~54 tok/s | ~130 tok/s |
Fit means the weights plus an 8K context cache fit in memory; speed is the estimated decode rate. Prices are the cheapest live eBay listing that passed our filters, item plus shipping. How we estimate.