Thanks Boomie !

Awesome guy , he warned me about their rulles and about the seed , really nice person.

I would like to buy a redacted.ch invite , do you have any available ?

You really think that someone who can afford to own a hundred-node cluster would be interested in mining Bitcoins?

One thing that can topple the network is some bored Chinese technician trying to run the mining on one of their build-for-record-and-now-idle supercomputers. 7168 GPUs at ~500MH/s and 15000 CPUs at ~10MH/s would be 3.65TH/s, or a block every 10 minutes.

A cluster with 100 nodes, each with 2 dual-core Opteron 285 @2.6Ghz.
I was getting between 400 and 500 MH/s, couldn't occupy it for long and exclusively.
But a Radeon 5870 GPU in my home PC does 350 MH/s.

Compare:
Home PC - a small quiet box for ~$1000, 100 nodes cluster - a room with 8 noisy stands for about ~$1000000.

GPU mining is 100-1000 times cheaper for the same performance, both in money and in energy.

Was mining back in spring 2010, got 100 coins over a week with default CPU miner, eventually abandoned this as a waste of time...
Not the smartest decision, considering that i work at a place where i could easily get access to superclusters.
Well, you can't turn hindsight around.

Ok, then what about the times and rate limits?

This probably belongs to development forum, but lots have changed here over the last year apparently...
Two questions about network logic.

Can anyone explain to me why this scenario cannot happen:
The hashes are practically random, for every block there is 32 bit of nonce and 32bit of timestamp.
Can it happen so that none of 18446744073709551616 hashes that would be generateable from this set of variables would be below the target?
It sounds like a freak of luck for that to happen, is this considered or is deemed too unlikely?


Second, in practical terms, does this put a limit on generation rate at roughly 4.2 Ghash/s?
Once all the nonce is tried, the timestamp must be incremented, but a second is not done yet.

With network rate of ~10Thash/s, does that mean that there is a lot of redundant tries?
With deviation in time spread about +-5 minutes that's still 600 possible sets of 4.2 Ghash/sec domains, naturally with lots of repeats.
What have i missed?

That's the kind of quantum computer i had in mind.

The regular currencies can adapt, by using symmetric cryptography at the expense of usability for example, but what would become of purely electronic thing like bitcoins are?

Haven't found much on the topic there, so asking away.

Let's say i have a practicable quantum computer or other device capable of rapid factorization of large enough integers.
What are the consequences to a developed bitcoin network?
Any way it could let me cheat in generation?
Any way it would let me cheat in transactions?

With a device of this kind i can get the private key from public key, right?
So after receiving a bitcoin from someone, can i subsequently successfully fake a transfer of all there was on his side?