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michaelttoday at 6:22 AM4 repliesview on HN

> Power is only a small part, single digit, it will eventually matter but does not really today.

Sorta yes, sorta no.

A single 5090 consumes 450W - at Californian energy prices of $0.38 per kWh that's $0.17 per hour. And the card itself costs $4100 on amazon. So after 2.75 years running at full power 24/7 you'll have spent more on electricity than on the card. I would have thought most data centres being built today would have a design life longer than 3 years.

Of course you can throttle the cards to ~300W without losing too much performance. But also you need more than a single 24GB card to run most modern LLMs.


Replies

veralltoday at 7:20 AM

DC has wider margins than the 5090. by someone elses rough numbers (https://www.spheron.network/blog/gb300-nvl72-vs-gb200-nvl72-...) for GB300 rack:

> 132kW

> ~$3.7-4M

So about 300x the 5090's power but 1000x the price. Roughly 9 years for electricity to exceed price at $0.38 and datacenters will show up in areas with cheaper power than CA.

Omniusaspirertoday at 7:26 AM

Anyone seriously building out AI infrastructure I presume is paying nowhere near $.38/kWh which is extortionate. Utility scale solar is closer to $.02-.03/kWh, then maybe around ~$.10/kWh for natural gas peaker plants.

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inigyoutoday at 11:42 AM

GPU design life is commonly cited as about 3 years. The main driver is not physical degradation of the cards but the expectation they'll become obsolete with newer cards.

threatrippertoday at 7:33 AM

Also add electricity 50% on top for cooling the DC.