No it isn't.  The heat coming from the computer is exactly the same per kWh as from a electric furnace.

You may argue that some of the power is wasted as sound waves, but even the sound waves will get absorbed by the walls and get converted to thermal energy.  Moving air will collide with stationary air and generate heat as the flow calms down.  Even the light from LEDs will get absorbed by the surface it hits and converted to heat.  Every single milliwatt used by the computer is converted to heat.

The calculation is different for a heat pump (inverted AC), but a heat pump is not an electric furnace.

Finding Bitcoin blocks is a lottery.  You get a certain number of tickets every second, depending on your hardware speed.  Chances of winning this lottery is slim, but the winner gets 50 coins + fees of transactions in the block.

A pool is where many miners join forces and put all tickets they buy into a common pool.  When someone wins, the 50 coins and possibly the fees (some pool owners keep the fees) are shared among all participants based on how much each participant contributed.

A pool will typically find blocks more often than a solo miner, because the combined hardware power of the pool is so much larger than a single miner.  For each miner the result is the same in the long run, given that the pool owner takes no fees.  In practice solo mining is more profitable in the long run because a solo miner is only dependant on his own miner and network, and can even tolerate short network outages.  Fewer dependencies means fewer interruptions in mining.  Pools are down now and then, and even DDOSed quite often.

The Bitcoin network would be more robust if more people mined solo.  When pools are DDOSed, block rate slows down and transactions confirms slower as a result.

I don't think Bitcoin Central has been compromised either, or has it?  Free software as well. :-)

Now you are silly.  He lost 2% of his annual BTC revenue.  That's 1% of his total revenue, only that MtGox can not exchange BTC into fiat currency (i.e. trade) themselves.  That would be against regulations in Japan.  Since the stuff which can be bought for BTC is still quite limited, MtGox lost very little of practical value to them.  The users lost nothing.

Who would you rather trust for exchanging bitcoins?  Bitomat (all lost, saved by MtGox)?  Bitcoin7 (most lost, can get some back by revealing all possible details about your self and submitting naked photo)?  Tradehill (endorses spam, reveals your trades to the one who referred you)?

Most of MtGox' coins are in an offline securely stored wallet, as was demonstrated after the crack.  It can't be lost by a simple programming error.

I'm able to send funds to MtGox quite easily, and cheap as long as I transfer a decent sum.  To help people who don't need much or don't want to transfer money internationally, I offer BTC for sale cheap and simple for my local currency using a payment method which is simple, free, safe and quite fast (usually overnight) in my country.  If other Bitcoin users would do the same, bitcoins would be easily available in any amount all over the world.

MtGox supported SEPA for a long time, and I'm sure it will be back.  It has been my favourite way to get fiat money into an exchange for a long time.  Bitcoin Central still support SEPA, and here are a few others as well.  And it is quite easy to get hold of BTC via SEPA on #bitcoin-otc.  All exchanges accept BTC. :-)

Not true.  I may not have any coins, or I may have 101 coins, or 1000.  The power of variance.  By average solo mining will pay better, independent of hashrate and difficulty.  Blocks are found randomly.  No single result is certain or impossible.  Correctly applied statistics can help you predict averages and other properties over time for large samples.

Btw, the difficulty has been declining for months now.  By some people's (flawed) logic, solo mining pays less due to difficulty increase.  Should be very profitable when difficulty goes down then, or what? :-)

This should not come as a surprise.  Some of us warned here on this forum of errors and insecure design of Bitcoin7 from the beginning, some suspecting a scam.  People will hopefully learn, again, to not trust their money, Bitcoin or fiat, to strangers.  It should be obvious.

The card uses 19W.  About 0.7 Mhash/s per watt isn't very good, but not terrible either.  166 kWh/year for a 1:17 chance to win 50.fees bitcoins at current difficulty is not bad.  The power isn't free (I don't pay for it, but I care about it), but the alternative to mining is an electrical oven.  I don't care that much about 2.82 BTC a year either, providing no pool downtime or difficulty changes, but I would care about a anonymous virgin block of 50 + fees.

So what?  It will take even longer to get 50 + fees BTC when mining in a pool.  I may actually get the 50.something in the lifetime of the card.  With pooled mining I am certain not to.  My average income from this card will be higher than in a pool.  In reality it will probably be 0 from now, if the difficulty stays up, but it can also be any multiple of 50 (or 25, 12.5, etc) + fees.  If I used this in a pool, I'd get something like 2.82 BTC a year.  I'll rather invest my 2.82 coins in a 1 to 17 chance to win 50 + some.  A nice, anonymous virgin block just for myself.  :-)

Yes, it does.  Do the math.  Difficulty is irrelevant.  Difficulty only changes the average time between blocks in solo mining or price per share in pooled mining.  The effect is the same.  The chance of finding a block is just a bit higher with lower difficulty.

Statistics is often non-intuitive, but this shouldn't be.  When solo mining your average income for a given hashrate is proportional to the difficulty.  When pool mining your average income for a given hashrate is also proportional to the difficulty.  For the exact same reason.  This is true for any period, and when the change happens or the direction (higher or lower) doesn't matter.  It happens at the same time for everyone.

Solo mining is more profitable than pooled mining, and hashrate has absolutely nothing to do with it.  Solo mining only means higher variance, and low hashrate means variance may be a bit high for some.  My 13 Mhash/s 5450 fanless PCI card has paid for itself and the computer many times by mining solo since december last year.  Often takes a while between blocks now, but I can wait.  (Last block in May.)

Problema i Frankrike er  over, og på mtgox kan du no handle direkte med, og ta ut og setje inn, DKK og SEK.  Det går via ein bank i Sveits.  For NOK er mitt tilbod det beste.  Beste ask + 0,05 USD (under 1% ekstra) konvertert til NOK.  Akkurat no er det 32,05 NOK.  Ingen gebyr om du har ein norsk bankkonto.

Eg har ein bankkonto i Tyskland som eg har brukt til overføring til mtgox.  Då er sjølve bankoverføringa gebyrfri.  Eit vekslingsgebyr og eit lite uttaksgebyr på mtgox kjem uansett i tillegg.  Det er ikkje tvilsamt skattemessig so lenge du oppgjev den utanlandske kontoen i sjølvmeldinga.  (Eg oppga mine bitcoins i fjor.  Saka har gått vidare til Skattedirektoratet, som framleis prøvar å finne ut kva Bitcoin er..)
Ja.

The Swiftech MCP655 is a great pump.  It can be PWM controlled, and even controlled by the fan controller on the 5970 to keep a constant temperature on the card, or connected to a fan connector on the mainboard and controlled with a script.  It has a large controllable range from 1400 RPM to about 5000, and the actual RPM can also be read from sensors when it is connected to the mainboard.  I use a MCP655, and regulate it to keep my GPU temperature constant in changing flow and temperature conditions as the heat is distributed to various places or saved in a buffer tank.  (I heat my floors and pre-heat my hot water with my miner.)  It is relatively silent as well.  (Inaudible compared to typical fan noise from a 5970, not to mention two!)

I may need another MCP655 soon, btw.  I'm preparing another miner for heating my living room floor during winter.

Eg sel bitcoins for norske kroner på #bitcoins-otc.  Betaling med vanleg bankoverføring.  Fint om det kjem fleire norske seljarar der, for etterspurnaden er høg.  Eg kan òg kjøpe direkte av deg, sidan det av og til kan vere vanskeleg å skaffe nok i tide til alle kjøparane.  Pga uttaksgrensa på 100 BTC om dagen frå mtgox må eg ofte finne fleire kjelder for å skaffe nok i tide når det kjem mange store ordrar på ein gong.

Det går forresten fint å ta ut EUR frå mtgox til ein norsk bankkonto.  Det kostar deg 2% per veksling i ein eller to valutavekslingar (avhengig av om du har USD eller EUR på mtgox) og eit gebyr, og transaksjonen tek nokre dagar.

I trade a lot on #bitcoin-otc.  Works fine, but always check ident and ratings.  Long time users rated by many (beware of short time users with few and very high ratings by other short time users), can be considered safe.  Be very careful with anyone else.

Why would anyone who use A/C place the radiator indoors?  That would be incredibly stupid.  You can get a lot of tubing for a few dollars.  A crane to switch between an indoor and outdoor radiator doesn't cost much either, in case you need heating on cold days.

Electronics use less power when it runs colder, btw.  My computer use about 5% less power on water cooling than it did on fans due to lower chip temperatures.  That's 5% less heat.

No, it isn't.  A water cooled system with a decent radiator can be almost inaudible.

Not really.  Space is extremely good at being hot and cold at the same time.  Heat can only leave as radiation, and if you are in the path of the sun's rays, your thing in space will become very hot because there is no air or fluids to lead the heat away.

Even in total darkness in space, radiation is limited at our temperatures.  A perfect 10cm x 10cm black-body surface will only radiate about 8W at 80°C.  Enough to cool one of Art's ASICs, if it can stay out of sunlight (may have a slight power supply problem there) but not any modern GPU.  A GPU will not last long in the radiation in space anyway..