I'd guess now that it's moved to the wiki, the wiki is regarded as sufficiently sticky and this thread can be left as just a pointer to the wiki.

I'm not sure about the (Windows?) installer, as I simply unzip and go (Linux). However, as far as I understand it the application and the wallet are only connected in as much as the application assumes the wallet will be a given location (unless you tell it otherwise). So if you install a new version of the client it should just work fine with the existing wallet.

Best bet, obviously, would be to back up your wallet before installing, and if anything goes wrong roll back to the previous version of the client and restore the wallet from your backup.

I don't consider myself "deep pocketed", though I will admit I had never spent more than the bare minimum on graphics cards until I discovered bitcoin. Back in February I did some sums, and worked out that I could afford to buy a second-hand 5870 for £130 (about US $215). That included tax, and postage was another £5 or so. I figured that the worst case scenario was that I'd end up with a really good (by my standards!) graphics card. Best case scenario was that I'd make enough bitcoins to pay for the card. I've been lucky, both with bitcoin generation and the exchange rate, and I managed to pay for the card within a month or so.

Even with recent difficulty changes, I've tended to generate around three blocks per "difficulty", i.e. I reset my mental clock each time the difficulty changes (roughly once a fortnight). This "fortnight" (the one we're in now) I've not generated anything yet. Last fortnight I got 3 blocks - 2 solo mining, one mining as part of a pool (though I didn't get 50 bitcoins for pool mining). The fortnight before that I only mined in a pool, and I found 3 blocks (and made around 100 bitcoins).

So, to answer your first question, it's not necessary to have lots and lots of expensive GPUs to mine successfully. However, you might consider spending your money just buying bitcoins, rather than buying mining hardware. It depends on your level of interest and your needs. I felt I could justify buying one graphics card, I'm not so sure I could have justified buying several (though, in hindsight, it would have been very profitable).

Turning to your second question: this list and this calculator are very useful. use them to try different scenarios. For example, you mention 10 machines all with 5970s. You can fit more than one 5970 in each machine, but lets ignore than and just consider ten 5970s. Each 5970 has a Mhash/s rate of between 530 and 645: lets pick 560 as a conservative value. Ten 5970s will yield 5600 Mhash/s (10 x 560, obviously!) which will, according to the calculator, provide an average of one block (50 bitcoins) every 17 hours 32 minutes at current difficulty.

...but that's not enough information on its own. You also need to consider when the difficulty will change, and what it will change to. We don't know, but bitcoincharts.com has an estimate. It also has various exchange rates, which will help you work out what your 50 bitcoins every 17-18 hours are worth in your usual currency (the currency you probably use to pay for GPUs and other things!)

Hope this helps. Only you can really answer the questions you've asked, and even then you'll be making guesses based on what may or may not happen in the future. The best advice I can give is to not spend what you can't afford to lose: if you can afford to spend money on one new graphics card, and you're not concerned about that card paying for itself (and most people outside this forum probably never consider the prospect that a graphics card could pay for itself!) then a small investment in a GPU could be an excellent idea. If you're in a position to make a large investment, that could potentially be very profitable but equally could result in you losing the entire investment, then consider either buying bitcoins directly, or investing in several GPUs and the accompanying hardward (motherboards, power supplies etc).

Sorry, no, you're right. I'd missed the part about the non-6990s. However, both you and I missed the part about the larger PSU for the 6950/6970s.

It's 2 GPUs per rig. Adding 2 more GPUs would be adding one more rig, which would include a new PSU.

Ah, with you now. I suspect they could do it instantly, but they'd want a second mortgage and your first born child.

Slightly related: many, many years ago I had a communication problem with an Irish bank clerk. I wanted to know how long it would take for my cheque to clear. Eventually she snapped and explained that in Ireland they had these things called "computers" and as a result cheques cleared instantly. We're just phasing out cheques in the UK, just as it becomes possible for cheques to clear in less than three days - I suspect the UK has moved to steam-powered abacuses... :-)

I wouldn't count on it, and would recommend checking with NAB first (I assume you're sending from Oz?) That said, my experience of transfers between AUD and GBP is very positive - quicker than GBP transfers within the UK. The UK banking system seems to be more broken than the international banking system (if you can believe that...!)

Try 3 to 5 working days in the UK.

It typically takes three working days to transfer money between two different banks, assuming both banks are in the same "country" (e.g. both are in England, or both are in Scotland). If one was a Scottish bank (let's say the Clydedale Bank) and one was an English bank (let's say Yorkshire Bank) it would usually take a minimum of four working days.

And now the punchline: Clydesdale Bank and Yorkshire Bank are both subsidiaries of National Australia Bank.

I suspect it's just a typo. There's a serious issue facing us all today: Muslamic ray guns.

Seriously, this is a logical fallacy, like the "Marxists are materialist. Libertarians are materialists. Therefore libertarians are Marxists" fallacy above.

Anything beyond opinion, pilgrim? Hell, for all we know you may have a well thought-out and rational reason, one we could all get on board with. Let's have it!

I have very little opinion on this pool, as I don't use it. I'm just curious as to why you have this opinion, and seem so keen to share it multiple times. I'd like you to elaborate. Rather than just saying "don't use this pool" I'd like you to say "don't use this pool because ..."

Actually, that's pretty much all you do. No explanation why, just a quick attack and sidle off. Care to change that, and provide some more detail this time? Otherwise it's difficult to escape the view that you're just trolling.

OK, economically free. Because Singapore is effectively a one-party state: the Peoples Action Party has won every election since 1959. In the 1970s visitors with long hair had compulsory hair cuts at the airport. When I was last there, in the 1980s, opposition politicians were "confessing their sins" on TV. Freedom House rates Singapore as "partly free", The Economist rates it as a "hybrid regime", the third rank out of four, in its "Democracy Index". (via Wikipedia).

Socially and politically Singapore is hugely authoritarian. Australia and New Zealand are 3rd and 4th on the Heritage list, and I'd regard both of those as suspect in terms of freedom - but Singapore? Hong Kong? Really?

There's no such thing as local value. Forex is a global market. If it's possible for someone to profit from arbitrage, they'll do it.

I appreciate that you regard the USD as dead or dying. I feel much the same way about my own currency (GBP). But we're a small minority in a vast, global and free market. Forex is the largest and most liquid market in the world: last year the daily turnover was $4 trillion. That dwarfs bitcoin.

It's usual in forex to consider how much one currency buys. For example, in USD trades they're typically quoted in terms of how much non-USD can be purchased (the exception being GBP, for historical reasons). It's the same with BTC: because we tend to regard that as the more important of the two pairs, we consider how much of the other currency we can purchase for 1 BTC: 1 BTC = 0.7905 USD, 1 BTC = 0.5804 GBP, etc. I don't see that as a bad thing.

The advantage of OpenID is that you may not even need to sign up: it's entirely possible you already have an OpenID account (possibly without realising it). If you have, say, MySpace account, WordPress blog, Steam account, TypePad blog or Launchpad account then you'll already have an OpenID account. Check the list: there are lots more OpenID providers I've not listed, and the Wikipedia list is likely incomplete.

Sure, I get that, and the coins also lose their freshly minted, unspent shininess and it's a pain waiting for the sent coins to be confirmed. It seems like it's the best (only?) option for kindle, though.

If you manage to do that could you, with their agreement, post a summary here? I'd be interested, too. My knowledge of anarchism is primarily left-oriented, but it's very out of date. I know the broad historical themes, but not the current debates.

True. My thinking was to protect the wallet, rather than have it on a machine exposed to the 'net, but...

...if the machine is only opening a limited number of trusted ports (8332 and SSH) then I guess the risk is minimal.

OK, the part I was missing was people switch off their machines :-)

Could you have the mining rig automatically send bitcoins to another wallet? Then when your workstation was brought online you'd have access to the sent coins.

I think we get the first part, it's the use case in the second part I'm not sure about.

In my proposal (which may not satisfy your use case) you have a workstation running "bitcoin -server". You use it to send and receive bitcoins, monitor transactions, etc. You also have a separate mining rig which connects to the workstation. Your wallet only needs to be on one machine (the workstation).

I suspect there's some subtlety I'm not getting, which necessitates cloning the wallet...

Ah, got it (I think. I pluralised "mining rig"...)

OK, I'm not sure I do get it. It still sounds to me like the solution would be to have a miner run on one machine, and bitcoind run on the workstation-from-which-payments-will-be-made. From a security perspective, the miner would be in the DMZ, and the wallet/workstation would be behind the firewall. What's the security benefit from having a common wallet?