High error rate on Windows no matter what

[stanley]

I've previously posted here: http://forum.bitcoin.org/index.php?topic=22683.0

but that thread is now much too narrow in scope, so I decided to start a new one.

On Ubuntu, I'm running DiaboMiner and mining for slush.  It's working great, with less than 1% of my blocks being rejected, except for a mysterious problem where the hash rate drops from 70 to 50 Mhash/s after I close the laptop's lid for a while.  However, on Windows, I can't mine without an extremely high error rate.  With DiabloMiner, roughly 40% of my blocks are rejected.  On Phoenix, it's approximately 10%. I've tried ATI Stream v.2.1, v.2.4, Catalyst 10.11, and Catalyst 11.06.  There seems to be no difference in terms of error rate.

Has anybody else encountered the same problem? I'm really hoping that someone has a solution!

[fascistmuffin]

Is this when you close the laptop lid?

There might be some power saving issues popping up since Windows really likes to mess with power saving on laptops in general.

[stanley]

No, the error rate isn't affected by whether I close the lid, in either operating system.  In Ubuntu, the only effect of closing the lid seems to be a drop in hash rate (I've never figured out why).  In Windows, the computer always went into hibernation after 15 minutes, even after I disabled hibernation in power management.  I think I've fixed that problem, and I'm hoping that the computer will mine overnight.

[gigabytecoin]

Wow 40% rejection rate? Seriously?

Sounds like something turned off and you were mining stale solutions for a long period of time.

Check that your "power options" are not lowering the power on ANYTHING after ANY amount of time. Lots of new operating systems come setup with that "feature" these days. Ubuntu is one of them.

Good luck.

[Keichtech]

When you close the lid to the laptop it is putting it in a power save mode.
That is why you have the drop in performance.

If you are using the Catalyst control center to over clock you card try increasing the memory.
That might fix your issue.