Your estimation feels too high. It implies >1000% ROI on a GPU card (= $300k gross annual profit on a $30k card).

As a reference point, Z.ai is operating at 26% gross margin as of 1H26. So assuming ~90% gross margin is likely a bit off.

No, those $3 are on the high end. If you do not factor in hardware depreciation, at China's low electricity prices (largest variable cost and China has a surplus larger than many country's entire consumption) and with GB200 which is one of DeepSeek's main platforms, the operation cost is actually less than 50 cents per hour most likely. If you factor in hardware depreciation this rises significantly but almost certainly stays under 3 usd per hour, probably closer to 2.

Orinally it was an educated guess based on rental prices I've seen but Opus 5.5 and Gemini 3.8 Flash both arive at the same numbers based on DeepSeek's Zhihu post and GB200 specs. Around 30 cents before depreciation and $2 to 3.50 including it.