RTX 5090 workstation (1x 32 GB) vs Used RTX 4090 workstation (24 GB)

RTX 5090 workstation (1x 32 GB) · Used RTX 4090 workstation (24 GB)

Verdict
  • throughputThe RTX 5090 workstation (1x 32 GB) delivers approximately 52% 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 Used RTX 4090 workstation (24 GB) has approximately 41% lower total monthly cost (€27 against €46), for a C corporation in United States (federal).
  • 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.
  • recommendationThere is no single answer: the RTX 5090 workstation (1x 32 GB) is faster, the Used RTX 4090 workstation (24 GB) is cheaper to own, and the Used RTX 4090 workstation (24 GB) gives more throughput per euro of purchase price. Pick on whichever constraint actually binds you — interactive latency, monthly budget, or capacity headroom for larger models later.
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
RTX 5090 workstation (1x 32 GB)Used RTX 4090 workstation (24 GB)
Price (NL, incl. VAT)€3.332€2.071
Memory32 GB24 GB
Memory bandwidth1,792 GB/s1,008 GB/s
Achieved bandwidth1,419 GB/s (79%)806 GB/s (80%)
Nominal power700 W600 W
Measured load power640 W520 W
Idle power70 W60 W
Architecturediscrete gpudiscrete gpu
Model performance8 models run on both
Qwen3-Coder 30B-A3BQwen3 30B-A3BGemma 4 26B-A4Bgpt-oss-20bDeepSeek-R1-Distill 32BQwen3 32BQwen3.8 27BQwen3.6 27B
ModelRTX 5090 workstation (1x 32 GB)Used RTX 4090 workstation (24 GB)Winner
Qwen3-Coder 30B-A3B
30.532B (3.3B active)
~333–480 t/s
Q4_K_M
~234–336 t/s
MLX 4-bit
RTX 5090 workstation (1x 32 GB) +43%
Qwen3 30B-A3B
30.532B (3.3B active)
352 t/s
Q4_K_M
~234–336 t/s
MLX 4-bit
RTX 5090 workstation (1x 32 GB) +24%
Gemma 4 26B-A4B
25.806B (3.8B active)
~303–435 t/s
Q4_K_M
~209–301 t/s
MLX 4-bit
RTX 5090 workstation (1x 32 GB) +45%
gpt-oss-20b
20.915B (3.6B active)
419 t/s
MXFP4
~228–329 t/s
MXFP4
RTX 5090 workstation (1x 32 GB) +50%
DeepSeek-R1-Distill 32B
32.764B
~55.4–79.7 t/s
Q4_K_M
~34.7–49.9 t/s
MLX 4-bit
RTX 5090 workstation (1x 32 GB) +60%
Qwen3 32B
32.762B
~55.4–79.7 t/s
Q4_K_M
~34.7–49.9 t/s
MLX 4-bit
RTX 5090 workstation (1x 32 GB) +60%
Qwen3.8 27B
27.781B
~64.7–93.1 t/s
Q4_K_M
~37.8–54.4 t/s
Q4_K_M
RTX 5090 workstation (1x 32 GB) +71%
Qwen3.6 27B
27.781B
~64.7–93.1 t/s
Q4_K_M
~37.8–54.4 t/s
Q4_K_M
RTX 5090 workstation (1x 32 GB) +71%
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
RTX 5090 workstation (1x 32 GB)Used RTX 4090 workstation (24 GB)
Purchase price estimate$3,332$2,071
Reclaimable VAT$0$0
Net cash at purchase$3,332$2,071
Monthly depreciation$47.21$26.92
Monthly electricity$4.53 (32 kWh)$3.75 (27 kWh)
Tax programme§179 100.0%§179 100.0%
Tax-programme benefit$700$435
Monthly economic cost$45.51$26.84
Total over 5 years$2,731$1,611
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.