I can't believe this - you're doing this on purpose, aren't you?

There are certain syntactic rules governing Bitcoin addresses and you better hope to god that your mistyped address is in violation of them because otherwise your coins aren't in Kansas anymore.
There is absolutely no way whatsoever to forcibly undo any Bitcoin transaction.
Gotta pay attention to what you're doing, man, and - for crying out loud - learn to use copy&paste.

100 rejects per 1000 accepted shares is a terrible ratio (10%). You're wasting time and electricity on those failed shares.
100 / 10 000 starts being reasonable. My miners are closer to 100 / 100 000.

Is that a Windows machine? Are any errors or crashes being logged in the Event Viewer?
What miner are you using?

bidding 6 btc.

Roger that, I'll donate whenever I have unallocated bitcoins to spare, sir.

Another bitcoin donated: sendtoaddress 1BTC1oo1J3MEt5SFj74ZBcF2Mk97Aah4ac 1
7e13476b9c9617824e2c99b20af10701709deedcadf6b5002a626263a9536f81
Do you think you could set me up for donationLimit=NO_MAX?

Once you've logged in to intersango: Accounts -> Bitcoins -> Withdraw funds.
You just need to supply a valid Bitcoin address and the amount you want to withdraw.
You do have a Bitcoin address, right?

Utility... an indicator I didn't even consider. Sounds good.

Don't GPUs belong in the "main" hardware subforum kinda by default?
GPUs are by far the most common devices used for mining.

You're right about the CPU mining subforum, except I'd put it in Trash rather than Hardware

My approach stemmed from the fact that it was boozer who reported a range of horrible events like cards dying constantly, cgminer eating the whole available memory space and bringing the system to a screeching halt...
Oh and yes, using the API calls to interact with cgminer would be by far preferable - I never suggested using messenger pigeons or necromancy in the overseer script. 
The rest - such as actually detecting the pool-related issues remains the same, doesn't it? At least until the PoolIsInTrouble API is added.


*stroking DAT's head* good Death, wise Death. We're certainly glad to have thee aboard

Unfortunately, no.
This behavior can be achieved by writing an overseer script for cgminer:
(1) cgminer is launched with just one pool defined (your primary pool).
(2) in case of connectivity issues¹ cgminer is killed off and restarted with a share limit² and another pool (or set of pools) configured.
(3) upon hitting the share limit cgminer shuts down and the overseer repeats step 1.

Notes:
1. detected by e.g. measuring the GPU temperature drop and low GPU load. A more sophisticated approach could include looking for certain key phrases in cgminer output to detect a range of pool issues where the pool is crippled but not down.
2. alternatively, the overseer could kill cgminer when a time limit expires.

A very competent - if brief - overview of the Kepler architecture basics.
An excellent read which goes well with a cup of espresso.

My mistake with the 8-pin splitter, link removed. Ummm... no 8 pin PCIe splitters on NewEgg currently, damn it.

You can safely use the 6 pin to dual 6+2 pin adapter; the two additional ground wires don't carry any load worth mentioning.
The card checks whether they are connected to make sure a PCIe 6-pin connector hasn't been plugged into the 8-pin slot.

Here's why:

No sooner were the PCIe 6-pin connectors introduced into ATX spec (ATX12V v2.1, 2005) when video card manufacturers shocked the ATX committee by announcing they needed even more power and requesting the power limit be raised from 75W to 150W.

A potential issue was brought up where a PSU would deliver the 75W but couldn't handle the increased load of 150W due to rail load limits.
This necessitated introducing yet another connector - the PCIe 8 pin variety. As I already said, the two additional ground wires are merely being used as a safety device.

No semi-decent PSU today should have any problems with supplying 150 watts of power over the 12V rails so the threat 8-pin connectors had been developed to guard us from is irrelevant.

The electrical specs for both PCIe connectors are the same, there are three 12V wires and three ground wires. The connectors use Molex MiniFit Jr contacts, HCS variety, each good for 13A of current. From an engineering standpoint, those connectors are perfectly able to deliver a load of 375 watts indefinitely.

You could only get in trouble if the Chinese manufacturers of those adapters use subpar materials like thinner wire gauge or low quality contacts.
Regrettably, such unfair practices are not unheard of.

This one? You're in luck for that is a very decent PSU, you just need to get a PEG 8-pin splitter and perhaps a PEG 6-pin splitter.
Using PEG splitters is by far preferable to drawing power from the molex 4-pin peripheral connectors (three 12V wires instead of just one).

Make sure to measure the actual power usage once you have replaced one 5830 with a 5970 and don't go crazy with overclocking.

A piece of software by LogMeIn

Martona, if you got the executable from Con's homepage, you should be safe.

It definitely is a viable solution, except implementing it will be far from trivial.
Turn off any unused device in the BIOS for should you run out of resources at the BIOS level, there is nothing the OS can do - some GPUs will remain uninitialized / unmapped into memory.
Far easier to use two systems with 4 cards each.

Would you agree there is a distinct possibility that boards with multiple GPU slots may have been designed with maximum flexibility in mind?

Make sure you have a copy of %appdata%\bitcoin\wallet.dat somewhere safe as this file holds all your private keys.
Uninstall the bitcoin client and remove the %appdata%\bitcoin directory.
Reinstall the client and try to re-download the blockchain.
You can swap in the backed-up wallet.dat later on if you succeed.

Frankly, I'm wondering whether the fact you're running an 11 year old OS with no AV protection and no firewall might have something to do with your current predicament.

Do you have another machine you could install the client on?
Install the client (don't launch it yet), create the %appdata%\bitcoin directory and place a copy of the wallet.dat inside it, then launch the client and wait until it downloads the blockchain.

BTW, you can download the blockchain yourself from the project's sourceforge page.

Wow, with that much information I can only suggest that you change ANYTHING, starting with cgminer kernel configuration and ending with the whole OS

EDIT::In case you missed it, a lot of GCN-related info can be found here and here.

Actually, you have it all backwards: a compromised host OS might very well have access to each and every file in the virtual machine - it's only a matter of what capabilities the malware has.
Your approach raises the bar by making your machine non-standard, but no VM vendor can guarantee that the clean virtual machine will remain safe when ran on a compromised system.
While an additional degree of security is certainly nice to have, you should not depend on it.

Virtual machines are usually deployed in exactly the opposite scenarios: to contain a threat and prevent it from leaking to the host OS.

The ugly marketing tricks are back, this time courtesy of Antec.
While boasting 80 PLUS Platinum certification on the box, by the vendor's own admission efficiency of only 87 to 90% (i.e. Gold) is to be expected from the retail units.

In other words, a superior hand-picked sample was sent for 80 PLUS certification.
While it is the manufacturer's prerogative to do so, such attitude towards the end users should be pointed out and stigmatized as unfair competition.

Other manufacturers whose units had reached unexpectedly high certification levels (e.g. SilverStone or Corsair with their HX850) opted to stick with the lower certification level as more representative of the typical efficiency of their products, as a fair play gesture.

Priced at $260, the Antec HCP 1000W is tied with the renowned Seasonic Platinum 1000W and significantly more expensive than most Gold certified units⁽¹⁾.
In fact, it is even more expensive than the Kingwin LZP 1000W meeting its rated (Platinum) efficiency, and merely $6 less expensive than the Seasonic-manufactured XFX ProSeries 1250W.

While Delta-manufactured Antec HCP 1000W is without a doubt an excellent PSU well worth recommending, a store-bought unit is very unlikely to reach the 80 PLUS Platinum efficiency levels.
Apples to apples, Antec - doling out the big bucks for a mining PSU I'd really prefer the unit to be able to meet its advertized efficiency.

Notes:
(1) there are five links here, mind you.

I don't know - nor have I said anything - about the client being certified, but I am well aware who's acting as if they are certifiable...
Electrum is a well-known open source project, for crying out loud: grab the source, study it, compile and install when you have satisfied yourself that it is safe.

As a general piece of advice, taking a more humble approach when asking for help might be a strategy well worth considering.