Mac Studio M5 Ultra 256 GB vs Mac Studio M5 Ultra 96 GB
Verdict
- throughputThe Mac Studio M5 Ultra 96 GB delivers approximately 15% higher aggregate decode throughput across the 8 models both machines can run (geometric mean of the per-model ratios).
- capacityBoth machines run all 8 compared models, so this is a pure speed and cost decision rather than a capability one.
- costAt 8 hours a day, the Mac Studio M5 Ultra 96 GB has approximately 31% lower total monthly cost (€62 against €90), for a C corporation in United States (federal).
- evidenceEvery throughput figure in this comparison is estimated. Treat the ranking as indicative and the margins as unreliable.
- recommendationThe Mac Studio M5 Ultra 96 GB is both faster and cheaper to own here, so it is the straightforward choice unless you need something specific to the Mac Studio M5 Ultra 256 GB.
Every statement above is generated from the calculations on this page by fixed rules — no prose is written for individual comparisons. If the numbers change, the verdict changes with them.
Hardware
| Mac Studio M5 Ultra 256 GB | Mac Studio M5 Ultra 96 GB | |
|---|---|---|
| Price (NL, incl. VAT) | €8.647 | €5.945 |
| Memory | 256 GB | 96 GB |
| Memory bandwidth | 1,200 GB/s | 1,200 GB/s |
| Achieved bandwidth | 1,052 GB/s (88%) | 1,052 GB/s (88%) |
| Nominal power | 300 W | 280 W |
| Measured load power | 215 W | 190 W |
| Idle power | 13 W | 12 W |
| Architecture | unified memory | unified memory |
Model performance8 models run on both
Qwen3.5 122B-A10Bgpt-oss-120bQwen3-Coder 30B-A3BQwen3 30B-A3BGemma 4 26B-A4Bgpt-oss-20bLlama 3.3 70BDeepSeek-R1-Distill 32B
| Model | Mac Studio M5 Ultra 256 GB | Mac Studio M5 Ultra 96 GB | Winner |
|---|---|---|---|
| Qwen3.5 122B-A10B 125.086B (10B active) | ~63.6–91.6 t/s Q8_0 | ~112–162 t/s MLX 4-bit | Mac Studio M5 Ultra 96 GB +43% |
| gpt-oss-120b 116.829B (5.1B active) | ~203–293 t/s MXFP4 | ~203–293 t/s MXFP4 | Tie (0%) |
| Qwen3-Coder 30B-A3B 30.532B (3.3B active) | ~167–240 t/s Q8_0 | ~167–240 t/s Q8_0 | Tie (0%) |
| Qwen3 30B-A3B 30.532B (3.3B active) | ~167–240 t/s Q8_0 | ~167–240 t/s Q8_0 | Tie (0%) |
| Gemma 4 26B-A4B 25.806B (3.8B active) | ~149–214 t/s Q8_0 | ~149–214 t/s Q8_0 | Tie (0%) |
| gpt-oss-20b 20.915B (3.6B active) | ~261–376 t/s MXFP4 | ~261–376 t/s MXFP4 | Tie (0%) |
| Llama 3.3 70B 70.554B | ~11.3–16.3 t/s Q8_0 | ~19.7–28.3 t/s Q4_K_M | Mac Studio M5 Ultra 96 GB +42% |
| DeepSeek-R1-Distill 32B 32.764B | ~24–34.6 t/s Q8_0 | ~24–34.6 t/s Q8_0 | Tie (0%) |
Differences under 10% are reported as a tie: they are smaller than the spread between published benchmarks of the same configuration, so calling a winner would be false precision. Rows where a model fits on only one machine are decided by capacity, not speed.
Economics — United States (federal), C corporation, 8h/day
| Mac Studio M5 Ultra 256 GB | Mac Studio M5 Ultra 96 GB | |
|---|---|---|
| Purchase price estimate | $8,647 | $5,945 |
| Reclaimable VAT | $0 | $0 |
| Net cash at purchase | $8,647 | $5,945 |
| Monthly depreciation | $100.88 | $69.35 |
| Monthly electricity | $1.32 (9 kWh) | $1.17 (8 kWh) |
| Tax programme | §179 100.0% | §179 100.0% |
| Tax-programme benefit | $1,816 | $1,248 |
| Monthly economic cost | $90.39 | $62.35 |
| Total over 5 years | $5,424 | $3,741 |
Tax assumptions last verified 2026-09-07. Federal planning estimate only, not tax advice. State and local income tax, sales/use tax and incentives are excluded. It assumes 100% business use, a Section 179 election, enough business income to use it, and that the full annual limit remains available.