Mac Studio M3 Ultra 256 GB vs Mac Studio M3 Ultra 96 GB
M3 Ultra 256 GB has 256 GB memory, 819 GB/s bandwidth, 270 W nominal power; M3 Ultra 96 GB has 96 GB memory, 819 GB/s bandwidth. Compare model compatibility, like-for-like tokens/sec and ownership cost below.
Verdict
- throughputNo valid like-for-like performance comparison is available. The practical configurations below differ in quantization, runtime, context, settings, or evidence type, so their speed difference must not be attributed to hardware alone.
- capacityBoth machines run all 8 compared models in their best practical configurations. Compare their quantizations and evidence labels before treating any throughput difference as a hardware result.
- costAt 8 hours a day, the Mac Studio M3 Ultra 96 GB has approximately 100% lower total monthly cost ($0 against $60), for a C corporation in United States (federal).
- evidenceThere are no comparable throughput rows, so this page makes no hardware-speed ranking. Practical deployment figures remain useful for fit planning but answer a different question.
- recommendationThroughput is close enough to be a wash, so this comes down to cost and capacity: the Mac Studio M3 Ultra 96 GB is cheaper to own, and capacity differences above decide which models you can run at all.
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 M3 Ultra 256 GB | Mac Studio M3 Ultra 96 GB | |
|---|---|---|
| Purchase price estimate | $5,674 * | — |
| Memory | 256 GB | 96 GB |
| Memory bandwidth | 819 GB/s | 819 GB/s |
| Usable bandwidth indicator | 580 GB/s (71%) | 580 GB/s (71%) |
| Nominal power | 270 W | — |
| Measured load power | 195 W | — |
| Idle power | 12 W | — |
| Architecture | unified memory | unified memory |
Like-for-like performance0 comparable models
Ternary Bonsai 2 27BQwen3.5 122B-A10BNemotron 3 Super 120B-A12BMistral Small 4 119B-A6.5Bgpt-oss-120bMixtral 8x7BPhi-3.5 MoE 42B-A6.6BNemotron 3.5 Lightning 30B-A3B
| Model | Mac Studio M3 Ultra 256 GB | Mac Studio M3 Ultra 96 GB | Winner |
|---|---|---|---|
| Ternary Bonsai 2 27B 27.36B | — no matched configuration | — no matched configuration | Not comparable |
| Qwen3.5 122B-A10B 125.086B (10B active) | — no matched configuration | — no matched configuration | Not comparable |
| Nemotron 3 Super 120B-A12B 123.611B (12B active) | — no matched configuration | — no matched configuration | Not comparable |
| Mistral Small 4 119B-A6.5B 119.401B (6.5B active) | — no matched configuration | — no matched configuration | Not comparable |
| gpt-oss-120b 116.829B (5.1B active) | — no matched configuration | — no matched configuration | Not comparable |
| Mixtral 8x7B 46.703B (13B active) | — no matched configuration | — no matched configuration | Not comparable |
| Phi-3.5 MoE 42B-A6.6B 41.873B (6.6B active) | — no matched configuration | — no matched configuration | Not comparable |
| Nemotron 3.5 Lightning 30B-A3B 31.578B (3B active) | — no matched configuration | — no matched configuration | Not comparable |
Hardware deltas are calculated only when quantization, runtime, exact context, execution/decode mode and relevant inference settings match. Measured and estimated results are never compared to each other. A difference under 10% is reported as a tie.
Best practical configuration
| Model | Mac Studio M3 Ultra 256 GB | Mac Studio M3 Ultra 96 GB | Practical result |
|---|---|---|---|
| Ternary Bonsai 2 27B | — PTQ1_0 · estimated | — PTQ1_0 · estimated | Both fit; configurations may differ |
| Qwen3.5 122B-A10B | ~36.4–52.3 t/s Q8_0 · estimated | — MLX 4-bit · estimated | Both fit; configurations may differ |
| Nemotron 3 Super 120B-A12B | ~30.5–43.9 t/s Q8_0 · estimated | — MLX 4-bit · estimated | Both fit; configurations may differ |
| Mistral Small 4 119B-A6.5B | ~54.6–78.6 t/s Q8_0 · estimated | — Q4_K_M · estimated | Both fit; configurations may differ |
| gpt-oss-120b | ~126–182 t/s MXFP4 · estimated | — MXFP4 · estimated | Both fit; configurations may differ |
| Mixtral 8x7B | — Q8_0 · estimated | — Q8_0 · estimated | Both fit; configurations may differ |
| Phi-3.5 MoE 42B-A6.6B | — Q8_0 · estimated | — Q8_0 · estimated | Both fit; configurations may differ |
| Nemotron 3.5 Lightning 30B-A3B | ~110–158 t/s Q8_0 · estimated | — Q8_0 · estimated | Both fit; configurations may differ |
This is a deployment comparison: each machine uses its own recommended configuration. Different quantizations can change speed and quality, so these figures are not raw hardware benchmarks.
Economics — United States (federal), C corporation, 8h/day
| Mac Studio M3 Ultra 256 GB | Mac Studio M3 Ultra 96 GB | |
|---|---|---|
| Purchase price estimate | $5,674 | — |
| Reclaimable VAT | $0 | $0 |
| Net cash at purchase | $5,674 | $0 |
| Monthly depreciation | $66.20 | $0.00 |
| Monthly electricity | $1.20 (9 kWh) | $0.00 (0 kWh) |
| Tax programme | §179 100.0% | §179 100.0% |
| Tax-programme benefit | $1,192 | $0 |
| Monthly economic cost | $59.58 | $0.00 |
| Total over 5 years | $3,575 | $0 |
Purchase prices are localized inputs in USD: tax/VAT excluded for Mac Studio M3 Ultra 256 GB and tax/VAT excluded for Mac Studio M3 Ultra 96 GB. Net cash and monthly economic cost then apply the selected United States (federal) / C corporation tax treatment. 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.