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Comment by mvkel | Hacker News Reader

Sort of.

An imperfect analogy: a small neighborhood of ~15 houses is under construction. Normally it might have a 200kva transformer sitting at the corner, which provides appropriate power from the grid.

But there is a transformer shortage, so the contractor installs a commercial grade 1250kva transformer. It can power many more houses than required, so it's operating way under capacity.

One day, a resident decides he wants to start a massive grow farm, and figures out how to activate that extra transformer capacity just for his house. That "activation" is what geohot found

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That's a poor analogy. The feature is built in to the cards that consumers bought, but Nvidia is disabling it via software. That's why a hacked driver can enable it again. The resident in your analogy is just freeloading off the contractor's transformer.

Nvidia does this so that customers that need that feature are forced to buy more expensive systems instead of building a solution with the cheaper "consumer-grade" cards targeted at gamers and enthusiasts.

This isn’t even the first time a hacked driver has been used to unlock some HW feature - https://github.com/DualCoder/vgpu_unlock

There was also this https://hackaday.com/2013/03/18/hack-removes-firmware-crippl... using resistors and a different one before that used a graphene lead pencil to enable functionality.

Except that in the computer hardware world, the 1250 kVA transformer was used not because of shortage, but because of the fact that making a 1250 kVA transformer on the existing production line and selling it as 200 kVA, is cheaper than creating a new production line separately for making 200 kVA transformers.

And then because this residential neighborhood now has commercial grade power, the other lots that were going to have residential houses built on them instead get combined into a factory, and the people who want to buy new houses in town have to pay more since residential supply was cut in half.

This represents pretty well how gamers (residential buyers) are going to feel when the next generation of consumer cards are scooped up for AI.

Excellent analogy of the other side of this issue.

That's a bad analogy, because in your example, the consumer is using more of a shared resource (the available transformer, wiring, and generation capacity). In the case of the driver for a local GPU card, there's no sharing.

A better example would be one in which the consumer has a dedicated transformer. For instance, a small commercial building which directly receives 3-phase 13.8 kV power; these are very common around here, and these buildings have their own individual transformers to lower the voltage to 3-phase 127V/220V.

Where is the hack in this analogy

Taking off the users panel on the side of their house and flipping it to 'lots of power' when that option had previously been covered up by the panel interface.

Except that this "lots of power" option does not exist. What limits the amount of power used is the circuit breakers and fuses on the panel, which protect the wiring against overheating by tripping when too much power is being used (or when there's a short circuit). The resident in this analogy would need to ensure that not only the transformer, but also the wiring leading to the transformer, can handle the higher current, and replace the circuit breaker or fuses.

And then everyone on that neighborhood would still lose power, because there's also a set of fuses upstream of the transformer, and they would be sized for the correct current limit even when the transformer is oversized. These fuses also protect the wiring upstream of the transformer, and their sizing and timings is coordinated with fuses or breakers even further upstream so that any fault is cleared by the protective device closest to the fault.

There are analogies, and then there's this.

They're pointing out how the analogy doesn't work, so it's fine.

Nobody's taking more than their share of any resources when they enable this feature.

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