Quad RTX 5090 workstation (4x 32 GB) vs RTX 5090 workstation (1x 32 GB)
Quad RTX 5090 workstation (4x 32 GB) · RTX 5090 workstation (1x 32 GB)
Verdict
- throughputAcross the 8 models both machines can run, aggregate decode throughput is within 10% — close enough that the difference is smaller than the uncertainty in the underlying benchmarks.
- 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 RTX 5090 workstation (1x 32 GB) has approximately 73% lower total monthly cost (€46 against €170), for a C corporation in United States (federal).
- powerThe Quad RTX 5090 workstation (4x 32 GB) draws 2250 W under load against 640 W for the RTX 5090 workstation (1x 32 GB) — a 3.5× difference that shows up in the electricity line and in how loud and hot the room gets.
- evidence2 of 8 model rows have at least one real measurement behind them; the rest are estimated from memory bandwidth. Margins below roughly 20% should not decide a purchase.
- 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
| Quad RTX 5090 workstation (4x 32 GB) | RTX 5090 workstation (1x 32 GB) | |
|---|---|---|
| Price (NL, incl. VAT) | €12.611 | €3.332 |
| Memory | 128 GB | 32 GB |
| Memory bandwidth | 7,168 GB/s | 1,792 GB/s |
| Achieved bandwidth | 5,675 GB/s (79%) | 1,419 GB/s (79%) |
| Nominal power | 2600 W | 700 W |
| Measured load power | 2250 W | 640 W |
| Idle power | 190 W | 70 W |
| Architecture | 4× GPU | discrete gpu |
Model performance8 models run on both
Qwen3-Coder 30B-A3BQwen3 30B-A3BGemma 4 26B-A4Bgpt-oss-20bDeepSeek-R1-Distill 32BQwen3 32BGemma 4 31BQwen3.8 27B
| Model | Quad RTX 5090 workstation (4x 32 GB) | RTX 5090 workstation (1x 32 GB) | Winner |
|---|---|---|---|
| Qwen3-Coder 30B-A3B 30.532B (3.3B active) | ~301–434 t/s Q8_0 | ~333–480 t/s Q4_K_M | Tie (10%) |
| Qwen3 30B-A3B 30.532B (3.3B active) | ~301–434 t/s Q8_0 | 352 t/s Q4_K_M | Tie (4%) |
| Gemma 4 26B-A4B 25.806B (3.8B active) | ~281–404 t/s Q8_0 | ~303–435 t/s Q4_K_M | Tie (7%) |
| gpt-oss-20b 20.915B (3.6B active) | ~387–556 t/s MXFP4 | 419 t/s MXFP4 | Quad RTX 5090 workstation (4x 32 GB) +12% |
| DeepSeek-R1-Distill 32B 32.764B | ~65.3–94 t/s Q8_0 | ~55.4–79.7 t/s Q4_K_M | Quad RTX 5090 workstation (4x 32 GB) +18% |
| Qwen3 32B 32.762B | ~65.3–94 t/s Q8_0 | ~55.4–79.7 t/s Q4_K_M | Quad RTX 5090 workstation (4x 32 GB) +18% |
| Gemma 4 31B 31.273B | ~68.1–98 t/s Q8_0 | ~62.1–89.4 t/s MLX 4-bit | Tie (10%) |
| Qwen3.8 27B 27.781B | ~75.5–109 t/s Q8_0 | ~64.7–93.1 t/s Q4_K_M | Quad RTX 5090 workstation (4x 32 GB) +17% |
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
| Quad RTX 5090 workstation (4x 32 GB) | RTX 5090 workstation (1x 32 GB) | |
|---|---|---|
| Purchase price estimate | $12,611 | $3,332 |
| Reclaimable VAT | $0 | $0 |
| Net cash at purchase | $12,611 | $3,332 |
| Monthly depreciation | $178.65 | $47.21 |
| Monthly electricity | $14.83 (106 kWh) | $4.53 (32 kWh) |
| Tax programme | §179 100.0% | §179 100.0% |
| Tax-programme benefit | $2,648 | $700 |
| Monthly economic cost | $170.40 | $45.51 |
| Total over 5 years | $10,224 | $2,731 |
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.