The Rent-vs-Buy Index
One number we track every month: how many hours of use it takes for owning a used RTX 3090 to beat renting a 4090-class cloud GPU. Below that line, rent. Above it, buy. All prices are dated and sourced — and the history table grows each month, so you can see which way the market is moving.
As of August 1, 2026: a used RTX 3090 (~$680) beats renting a 4090-class cloud GPU (~$0.27/hr) once you use it more than ~3,063 hours — about 2.1 years at 4 hours/day. Below that, renting is cheaper; above it, owning wins and every further hour costs only ~$0.05 in electricity.
What that means at your usage
Break-even is usage-independent (~3,063 hours); only the calendar time to reach it changes. Run your own numbers in the rent-vs-buy calculator.
How the index has moved
| Month | Used 3090 | 4090 cloud /hr | Break-even hrs | Δ |
|---|---|---|---|---|
| Jun 29, 26 | $700 | $0.29 | 2,954 | — |
| Aug 1, 26 | $680 | $0.27 | 3,063 | +109 |
How this is measured
Break-even hours = purchase price ÷ (cloud $/hr − local $/hr), where local $/hr is active draw (320 W) × electricity rate ($0.15/kWh). Depreciation is conservatively treated as sunk cost. The full model is in the rent-vs-buy break-even guide; provider-by-provider rental options are in the cloud-GPU reviews. Prices are community-cited and dated, not independently verified — see methodology.
- Buy: eBay used RTX 3090 24GB sold listings, observed (2026-08-01)
- Rent: RunPod + Vast.ai pricing pages, observed (2026-08-01)
- Electricity: U.S. EIA average residential rate, 2025
Data as of August 1, 2026. Updated monthly.