I need some help: I just joined and have been mining for approximately 6 hours with four miners. I have chosen PPS. My statistics show no shares earned. The "lifetime" miner statistics register that work has been done, but no valid shares.

What am I missing?

One hint for anyone else using this: make sure that the Windows power setting has "turn off monitor" set to "never". Once the monitor powers off, the mining stops.

On another note, I have successfully gotten this to run, but it seems to work for only one GPU. Is there a way to make this work for more than one GPU?

I'll chime in because I had this frustration a few days ago.

All I did was use Windows (not CCC) Desktop Properties / Settings. Then I clicked on the second monitor and checked "Extend my windows desktop to this monitor". That enabled the second monitor.

The downside is that I now have an extended desktop where I can only see half of the desktop. I am unable to find a solution to mirror or duplicate the desktop so that I do not have a phantom extended desktop.

I think this is an excellent point. Pretend you are a pool operator out to cheat. Having 5 visibly bad days seems like a bad way to steal. It would be both easier and less visible to skim off a small amount on a constant basis rather than inserting code that robs a large amount on a set schedule.

I think questions should always be asked, so I don't begrudge you for putting forth the notion that BTC might be cheating.

However, people are notoriously poor judges of randomness. The "hot hand" in basketball is a classic example that statisticians use of sports fans attributing skill to what can be explained by a good run of randomness.

As you said, the luck suddenly shot up 70% for a day. Rather than focusing on the five days, it might make more sense to take an entire month, which includes the one good day and all the bad days. Put another way, I'm sure you know that flipping a coin and coming up with five heads proves nothing, even though the probability is 3%, which in the parlance of this post implies a 97% chance of cheating.

As a final note, your calculated probability of 0.6952% (which I have not verified) is well within a 4-sigma event (0.0165%). Four standard deviations is hardly considered extreme.

I have a satisfactory workaround for machines that are predominately idle: use BitcoinMinerSaver ( http://bitcointalk.org/?topic=8385.0 )

Details:
1) Set up BitcoinMinerSaver on all user accounts.
2) Install TweakUI 2.1. Under "Logon", there is an option to change the default screen saver for the logon screen. Use this option - it will then copy all screen saver options (which will be the Bitcoin miner) of the current user as the logon screen saver.
3) Reboot

Note that step "2)" is required because if users simply "switch user" instead of going idle (and letting that user's screen saver take over), then the default screen saver takes over rather than the user's screen saver. Step "2)" changes the default screen saver so that no matter which screen saver activates (User1's, User2's, or the Logon screen default screen saver), the miner runs.

Main drawbacks:
A) The BitcoinMinerSaver only works with one device.
B) Only works while idle.

I have two cards (Radeon 6970). One has a real monitor and the other has a dummy plug.

How does one get the Catalyst Control Center to duplicate the desktop rather than extend the desktop?

As I currently have it, the dummy-plugged monitor extends the desktop, which I can't see since it is a dummy monitor. I have right-clicked everything and can't seem to find a "mirror" or "duplicate" option.

I have reproduced the following problem several times. I am running poclbm and phoenix through guiminer on Windows XP. The configuration does not appear to matter. I have a Radeon 6850 and have tried Catalyst 11.4, 11.5, 11.6, and 11.7.

I have two user accounts on a machine ("user1" and "user2"). the miner is set up to run under "user1". With "user1" still running, if the machine switched users and "user2" logs in, the miner (poclbm or phoenix) freezes. Task Manager also shows poclbm or phoenix at 100% CPU utilization.

Anyone else see this or find a work around?

Is there a problem with two computers (each with the Bitcoin application installed) accessing a common wallet file which resides on a shared server?