Dual RTX 5090 workstation (2x 32 GB) vs RTX 5090 workstation (1x 32 GB)
Dual RTX 5090 has 64 GB memory, 3,584 GB/s bandwidth, 1,400 W nominal power; RTX 5090 has 32 GB memory, 1,792 GB/s bandwidth, 700 W nominal power. Compare model compatibility, like-for-like tokens/sec and ownership cost below.
Dual RTX 5090 workstation (2x 32 GB) · RTX 5090 workstation (1x 32 GB)
Verdict
- throughputAcross 4 like-for-like model configurations, decode throughput is within 10% — close enough that the difference is smaller than the uncertainty in the underlying evidence.
- 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 RTX 5090 workstation (1x 32 GB) has approximately 43% lower total monthly cost ($46 against $80), for a C corporation in United States (federal).
- powerThe Dual RTX 5090 workstation (2x 32 GB) draws 1180 W under load against 640 W for the RTX 5090 workstation (1x 32 GB) — a 1.8× difference that shows up in the electricity line and in how loud and hot the room gets.
- evidenceAll 4 like-for-like throughput rows are estimates. Treat the ranking as indicative and the margins as uncertain.
- recommendationThroughput is close enough to be a wash, so this comes down to cost and capacity: the RTX 5090 workstation (1x 32 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
| Dual RTX 5090 workstation (2x 32 GB) | RTX 5090 workstation (1x 32 GB) | |
|---|---|---|
| Purchase price estimate | $5,854 * | $3,332 * |
| Memory | 64 GB | 32 GB |
| Theoretical bandwidth (aggregate on multi-GPU) | 3,584 GB/s | 1,792 GB/s |
| Usable bandwidth indicator | interconnect-adjusted per workload | 1,419 GB/s (79%) |
| Nominal power | 1400 W | 700 W |
| Measured load power | 1180 W | 640 W |
| Idle power | 110 W | 70 W |
| Architecture | 2× GPU | discrete gpu |
Like-for-like performance4 comparable models
Ternary Bonsai 2 27BPhi-3.5 MoE 42B-A6.6BNemotron 3.5 Lightning 30B-A3BQwen3-Coder 30B-A3BQwen3 30B-A3BGemma 4 26B-A4Bgpt-oss-20bDeepSeek Coder V2 Lite 16B-A2.4B
| Model | Dual RTX 5090 workstation (2x 32 GB) | RTX 5090 workstation (1x 32 GB) | Winner |
|---|---|---|---|
| Ternary Bonsai 2 27B 27.36B | — 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) | ~308–443 t/s Q5_K_M | ~319–459 t/s Q5_K_M | Tie (4%) estimated · estimator_v1 · 8K context |
| Qwen3-Coder 30B-A3B 30.532B (3.3B active) | ~294–423 t/s Q5_K_M | ~299–430 t/s Q5_K_M | Tie (2%) estimated · estimator_v1 · 8K context |
| Qwen3 30B-A3B 30.532B (3.3B active) | ~294–423 t/s Q5_K_M | ~299–430 t/s Q5_K_M | Tie (2%) estimated · estimator_v1 · 8K context |
| Gemma 4 26B-A4B 25.806B (3.8B active) | ~273–393 t/s Q5_K_M | ~270–388 t/s Q5_K_M | Tie (1%) estimated · estimator_v1 · 8K context |
| gpt-oss-20b 20.915B (3.6B active) | — no matched configuration | — no matched configuration | Not comparable |
| DeepSeek Coder V2 Lite 16B-A2.4B 15.706B (2.4B 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 | Dual RTX 5090 workstation (2x 32 GB) | RTX 5090 workstation (1x 32 GB) | Practical result |
|---|---|---|---|
| Ternary Bonsai 2 27B | — PTQ1_0 · estimated | 121 t/s PTQ1_0 · measured | Both fit; configurations may differ |
| Phi-3.5 MoE 42B-A6.6B | — Q5_K_M · estimated | — Q4_K_M · estimated | Both fit; configurations may differ |
| Nemotron 3.5 Lightning 30B-A3B | ~249–359 t/s Q8_0 · estimated | ~319–459 t/s Q5_K_M · estimated | Both fit; configurations may differ |
| Qwen3-Coder 30B-A3B | ~236–339 t/s Q8_0 · estimated | ~299–430 t/s Q5_K_M · estimated | Both fit; configurations may differ |
| Qwen3 30B-A3B | ~236–339 t/s Q8_0 · estimated | ~299–430 t/s Q5_K_M · estimated | Both fit; configurations may differ |
| Gemma 4 26B-A4B | ~216–311 t/s Q8_0 · estimated | ~270–388 t/s Q5_K_M · estimated | Both fit; configurations may differ |
| gpt-oss-20b | ~324–466 t/s MXFP4 · estimated | 419 t/s MXFP4 · measured | Both fit; configurations may differ |
| DeepSeek Coder V2 Lite 16B-A2.4B | — 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
| Dual RTX 5090 workstation (2x 32 GB) | RTX 5090 workstation (1x 32 GB) | |
|---|---|---|
| Purchase price estimate | $5,854 | $3,332 |
| Reclaimable VAT | $0 | $0 |
| Net cash at purchase | $5,854 | $3,332 |
| Monthly depreciation | $82.94 | $47.21 |
| Monthly electricity | $7.98 (57 kWh) | $4.53 (32 kWh) |
| Tax programme | §179 100.0% | §179 100.0% |
| Tax-programme benefit | $1,229 | $700 |
| Monthly economic cost | $79.98 | $45.51 |
| Total over 5 years | $4,799 | $2,731 |
Purchase prices are localized inputs in USD: tax/VAT excluded for Dual RTX 5090 workstation (2x 32 GB) and tax/VAT excluded for RTX 5090 workstation (1x 32 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.