and it shows that at the current difficulty level, you should generate 50 BTC about every 3 days and 29 minutes.
So in a 24 hour period you get about 16.55 BTC per day.
Converting that 16.55 BTC to USD:
http://bitcoin.1t2l.net/widget/?from=BTC
shows you earn about $15.28 per day with a rig holding a single 5970.
Then to send those BTCs to your PayPal, you use http://coincard.ndrix.com (starting again monday morning) and you lose 3% doing that conversion so you end up with $14.82 in revenue per day. Subtract the $1.44 in electricity that nets you $13.38 a day. If that were to hold, you'ld have the card paid off in well under two months.
I was reading that the switch to generating 25 BTC at a time instead of 50 will happen very soon.
Even then, if you were only earning $7/day with a single 5970 rig, the payback period is not that long. It seems obviously worth doing, unless you think there will be a run on Bitcoin within the next 6 months or that a sudden move to ASIC will make GPU mining obsolete. I think I'm going to go for it. I might even take the risky investment and hold my bitcoins.
The switch to 25 BTC will happen at block 210,000, which will happen in January 2012. https://en.bitcoin.it/wiki/File:Total_bitcoins_over_time_gra...
Just like how GPU mining made CPU mining unprofitable, something else could come along and make GPU mining unprofitable. Probably couldn't happen before you've gotten your hardware purchase paid off though. Of course, if the exchange rate drops significantly, like the scenario pointed out here: ( http://mtgox.com/blog/?p=262 ) and doesn't recover for a while, you could end up never covering the cost of the equipment for your rig.
wow... I was all excited to try to generate some bitcoins, so I installed the software, checked the box to generate bitcoins, and walked away from my machine...
I come back a few days later and no bitcoins... I should have done a little bit more research because the rate I'm doing hashes on this old machine is a factor of 1000 slower than what people are getting out of GPUs. I'll be lucky if I generate 1 group of bitcoins in the next 10 years!
That's 12kWh at let's say a $0.12/kWh residential electric rate ( http://www.bitcoinminer.com/post/2361900289/where-to-mine-el... ) that's about $1.44 per day for your electricity.
A 5970 hashes at just under 600 Mhash/s, per http://en.bitcoin.it/wiki/Mining_hardware_comparison so punch that 600000 number in as khps here: http://www.alloscomp.com/bitcoin/calculator.php
and it shows that at the current difficulty level, you should generate 50 BTC about every 3 days and 29 minutes.
So in a 24 hour period you get about 16.55 BTC per day. Converting that 16.55 BTC to USD: http://bitcoin.1t2l.net/widget/?from=BTC shows you earn about $15.28 per day with a rig holding a single 5970.
Then to send those BTCs to your PayPal, you use http://coincard.ndrix.com (starting again monday morning) and you lose 3% doing that conversion so you end up with $14.82 in revenue per day. Subtract the $1.44 in electricity that nets you $13.38 a day. If that were to hold, you'ld have the card paid off in well under two months.
That said, ... difficulty is rising (fast! ... http://bitcoin.sipa.be/speed.png ). If the BTC/USD exchange rises more ( it's had quite a run http://bitcoincharts.com/charts/mtgoxUSD#rg60ztgSzm1g10zm2g2... ), then that payout might continue at these levels. Otherwise, the payout from mining will decrease.