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Re:Eight dormant Satoshi-era Bitcoin wallets reactivated aft... by onlyrealcuzzo on Friday July 04, 2025 @04:31PM (#44467650)
It would take approximately 6B H100 GPU days to crack every active BTC wallet.

So if you had 10,000 H100s running, it'd only take ~1500 years.

You'd have a high probability to find key in under ~1000 years, though.

Even if I'm off by 3 orders of magnitude, it would take a decade and cost billions, and not make financial sense.

Re:Eight dormant Satoshi-era Bitcoin wallets reactivated aft... by 1oooqooq on Friday July 04, 2025 @05:40PM (#44468076)
*at most ... years.

People always forget those numbers are worst case scenarios. I mean, you can get luck on the very first guess too.

Re:Eight dormant Satoshi-era Bitcoin wallets reactivated aft... by relaxing on Friday July 04, 2025 @07:04PM (#44468679)
If that’s the plan you can guess a number for free, no outlay needed.
Re:Eight dormant Satoshi-era Bitcoin wallets reactivated aft... by kelseyfrog on Friday July 04, 2025 @09:28PM (#44469417)
If your guess is generated by a QRNG and many worlds is true, than one version of you is very happy although the expected value is 1.03×10−66 USD.
Re:Eight dormant Satoshi-era Bitcoin wallets reactivated aft... by paulpauper on Friday July 04, 2025 @04:47PM (#44467768)
Active addresses have less entropy too
Re:Eight dormant Satoshi-era Bitcoin wallets reactivated aft... by FabHK on Saturday July 05, 2025 @07:56AM (#44472141)
Why? Are you hypothesizing that they used bad RNGs?
Re:Eight dormant Satoshi-era Bitcoin wallets reactivated aft... by FabHK on Saturday July 05, 2025 @02:24AM (#44470499)
How do you get that?

BTC private key space is 256 bit. Let's say a billion wallets, that's 30 bits, so you need to check 226 bits to hit one wallet.

A H100 does about 1000 TFLOPS at the very most, that's 10^15 or 50 bits per second (generously assuming we can check on key per FLOP).

6B days of that will give you an additional 50 bits (6 = 8 = 3 bits, B = 1000^3 = 30 bits, day = 10^5 seconds = 17 bits).

Now we're talking 100 bits. But as discussed above, you need to check 220 bits to hit a key. There's still quite a gap.

For comparison, the entire Bitcoin network (using 1% of world electricity) does about 1000 EH/s at the moment, that's 10^21 or 70 bits per second (so, roughly equivalent to a million of H100, using the rough overestimating sketch above).

Per year, that's 70+25 = 95 bits. Still far.