OFFICIAL CGMINER mining software thread for linux/win/osx/mips/arm/r-pi 4.11.1

[Lem]

I've noticed this thing since I have as my second and third (backup) pools two mtred servers:

Code:

1: Enabled Alive Priority 2: http://mtred.com:8337  User:lem98
2: Enabled Dead Priority 3: http://pa.mtred.com:8337  User:lem98

One of them is often dead, so I'm used to see that cgminer waits long before contacting next pools.

Yes that's intentional.

Ah, OK.

I think I will move those two pools to the last positions in my configuration file "pools" section: it should be pretty enough.

[Joshwaa]

Having problems with cgminer on a couple windows 7 machines. One that is running Win7 64 Hd7770. Whenever you q to quit the miner it reboots the computer instantly. No messages or anything. On all the other machines they are win 7 64 with HD58xx cards. After a random number of hours the miner keeps saying it is mining but no shares are submitted. I have to exit then restart. These are stratum connections to BTCGuild (no proxy). I did not have these problems on 2.7.6 when pointed to a stratum local proxy. Thanks for any help!

Computer rebooting I can't do anything about. It's clearly the driver crashing spectacularly since I couldn't write code that made computers blow up if I actually wanted to. You could try just closing the window instead of pressing q to quit.

Which version had the continuous hashing problem? That was a bug in 2.8.0 which is why I released 2.8.1 so soon after, fixing that precise bug.

I will re-download and try again.

[AxelMi]

Code:

[2012-10-09 15:10:46] Rejected ed5dd272 Diff 1 MM 4 pool 0 (lowdifficulty)
 [2012-10-09 15:10:46] Rejected 1c494208 Diff 1 MM 2 pool 0 (lowdifficulty)
 [2012-10-09 15:10:48] Rejected c1b3226d Diff 1 MM 3 pool 0 (lowdifficulty)
 [2012-10-09 15:10:48] Rejected 25398ba3 Diff 1 MM 8 pool 0 (lowdifficulty)
 [2012-10-09 15:10:48] Rejected 1507a8f3 Diff 1 MM 3 pool 0 (lowdifficulty)
 [2012-10-09 15:10:48] Pool 0 rejected 11 sequential shares, disabling!
 [2012-10-09 15:10:48] Switching to stratum+tcp://50.31.149.59:10332
 [2012-10-09 15:10:48] Rejected 65f05b02 Diff 1 MM 2 pool 0 (lowdifficulty)
 [2012-10-09 15:10:48] Rejected 454e85fe Diff 1 MM 10 pool 0 (lowdifficulty)
 [2012-10-09 15:10:49] Rejected e3379b73 Diff 1 MM 6 pool 0 (lowdifficulty)
 [2012-10-09 15:10:49] Rejected 5ea8c46e Diff 1 MM 0 pool 0 (lowdifficulty)
 [2012-10-09 15:10:50] Rejected 8bc9d1a6 Diff 1 MM 7 pool 0 (lowdifficulty)
 [2012-10-09 15:10:50] Rejected a6f05450 Diff 1 MM 1 pool 0 (lowdifficulty)
 [2012-10-09 15:10:50] Rejected e447138f Diff 1 MM 10 pool 0 (lowdifficulty)
 [2012-10-09 15:10:52] Rejected df3e89a8 Diff 1 MM 10 pool 0 (lowdifficulty)
 [2012-10-09 15:10:52] Rejected 0c93beef Diff 1 MM 1 pool 1 (lowdifficulty)
 [2012-10-09 15:10:52] Stratum from pool 1 requested work restart
 [2012-10-09 15:10:53] Rejected 0ba592a1 Diff 1 MM 0 pool 1 (lowdifficulty)
 [2012-10-09 15:10:53] Rejected 5cedef55 Diff 1 MM 11 pool 1 (lowdifficulty)
 [2012-10-09 15:10:54] Rejected 29fdaac6 Diff 1 MM 2 pool 1 (lowdifficulty)
 [2012-10-09 15:10:54] Rejected b41da195 Diff 1 MM 0 pool 1 (lowdifficulty)
 [2012-10-09 15:10:54] Rejected 2d612681 Diff 1 MM 2 pool 1 (lowdifficulty)
 [2012-10-09 15:10:55] Rejected 10b690af Diff 1 MM 1 pool 1 (lowdifficulty)
 [2012-10-09 15:10:56] Rejected ca76b883 Diff 1 MM 11 pool 1 (lowdifficulty)
 [2012-10-09 15:10:56] Rejected 7d0f83d0 Diff 1 MM 5 pool 1 (lowdifficulty)
 [2012-10-09 15:10:57] Rejected ff00f1aa Diff 1 MM 8 pool 1 (lowdifficulty)
 [2012-10-09 15:10:57] Rejected 79b66986 Diff 1 MM 6 pool 1 (lowdifficulty)
 [2012-10-09 15:10:57] Pool 1 rejected 11 sequential shares, disabling!
 [2012-10-09 15:10:57] Switching to http://pool.50btc.com:8332
 [2012-10-09 15:10:57] Long-polling activated for http://pool2.50btc.com:8331/LP

I am using 2.8.1 with an own Driver for my own Mining Hardware. With Stratum i am not able to connect to BTCGuild. My Hardware generates 12GH/sec. Also switching to an other Username on the pool doesn't help. Seems that my Diff is not increasing.
Any Ideas. Going now back to 2.7.5.

[mezzomix]

I'm running 2.8.1 now. It seems to me that stratum+tcp pools that fail once are marked as dead and never will become alive again.

Code:

 cgminer version 2.8.1 - Started: [2012-10-09 22:36:17]
--------------------------------------------------------------------------------
 (5s):11.3 (avg):11.1 Mh/s | Q:3376  A:158  R:6  HW:0  E:5%  U:0.1/m
 TQ: 0  ST: 3  SS: 1  DW: 575  NB: 109  LW: 5813  GF: 5  RF: 1  WU: 0.1
 Connected to http://mining.eligius.st:8337 with LP as user <user>
 Block: 000003b4be07550c78f0b88a71d20b77...  Started: [17:32:35]
--------------------------------------------------------------------------------
 [P]ool management [G]PU management [S]ettings [D]isplay options [Q]uit
 GPU 0:  71.0C         |  11.2/ 11.1Mh/s | A:158 R:6 HW:0 U:0.14/m I: 9
--------------------------------------------------------------------------------

0: Enabled Dead Priority 0: api-stratum.bitcoin.cz  User:<user>
1: Enabled Dead Priority 1: stratum.btcguild.com  User:<user>
2: Enabled Alive Priority 2: http://mining.eligius.st:8337  User:<user>

Current pool management strategy: Failover
[F]ailover only disabled
[A]dd pool [R]emove pool [D]isable pool [E]nable pool
[C]hange management strategy [S]witch pool [I]nformation
Or press any other key to continue

When I stop cgminer and start it again, the first stratum pool in my list is alive again. The second stratum pool in the list is always dead.

Code:

0: Enabled Alive Priority 0: api-stratum.bitcoin.cz  User:<user>
1: Enabled Dead Priority 1: stratum.btcguild.com  User:<user>
2: Enabled Alive Priority 2: http://mining.eligius.st:8337  User:<user>

[Joshwaa]

You need to add ":9332" after the stratum.btcguild.com   This might help, just a guess.

[mezzomix]

In my pool config the btcguild entry uses this port (see my pool config). It's only the UI, that is not showing the full configuration entries.

[SiegeBreaker]

For me, whatever changes happened to dynamic in 2.7.6 have made it work poorly again. It is back to being really unresponsive to lowering when I am using the gpu for other things. It will lower one intensity or even stay the same as when I am not using the gpu for something else. I am on Windows 7 with two 5870s. What specifically changed with the algorithm in 2.7.6?

(2.7.5 is running smooth, and responds quickly when other programs use the gpu, and all I have to do on that version is set the intensity to fixed then back to dynamic and I never get the negative intensity bug anymore. 2.7.5 is the first version since 2.1.2 that I can get high performance when not using the gpu for other things and still have really responsive backing off of intensity when I do).

[RandomQ]

Error -6 cl Create Command Queue on winblows

This is usually a bad or corrupted video driver right?

I've had this on a machine in the past, and just did a fresh OS to clean it.

Thanks for your response

[Maniac]

I have problem with mining litecoins on some my rigs.
My 6 rigs mining very great.

For example:

GPU: 6870, 6870, 6770, 6770
Mobo: Asrock 890 FX Deluxe 5
RAM: 2 Gb
OS: Win7 64
Drivers: 11.12 with OCL libs from 11.11 (for mining bitcoins when it more profitable)

cgminer.cmd (I use same copies of cmd's on all my rigs and it works very well)
cgminer --scrypt --worksize 256 --shaders 1280 --lookup-gap 2 -g 1 --thread-concurrency 8192 --intensity 17 -o http://ltc.xurious.com:9332 -u user -p pass

Screenshot (the picture is clickable):
Xocтинг фoтoгpaфий


But there is one problem rig:

GPU: 6870, 6770
Mobo: Asus P5KPL AM SE
RAM: 1 Gb
OS: Win7 64
Drivers: 11.12 with OCL libs from 11.11

This rig mining bitcoins without any problems (I use phoenix 2.7.5).

But there are problems with mining litecoins. I tried also reaper (it works better on my rig with 7970) but not good too.

When I start cgminer.cmd it does not work:

Xocтинг фoтoгpaфий


If I change cgminer.cmd to
cgminer --scrypt --worksize 256 --shaders 1280 --lookup-gap 2 -g 1 --thread-concurrency 2048 --intensity 12 -o http://ltc.xurious.com:9332 -u user -p pass
it work, but hashrate is very very low.

If I up --thread-concurrency, it does not work.

If I up --intensity, it makes HW and not makes accepted shares:

Xocтинг фoтoгpaфий


I tried versions 2.7.4, 2.7.5, 2.7.6 and 2.8.1.

Help me, please.
While my GPU can't mining litecoins I am very unhappy.
Thank you.

[P_Shep]

After 13 days non-stop operation, cgminer rotate has stopped rotating. Stuck on one pool now.

[wind]

Last time this happened it was a packaging error on my part. I'll reupload shortly. I've reuploaded it.

ckolivas I've just downloaded the last zipped source from your git but the problem is

Code:

 OpenCL...............: NOT FOUND. GPU mining support DISABLED

That's a different one and a problem with your installation lacking the AMD APP SDK, or you lack including the directories (with -I) you have the sdk installed into.

ckolivas
Compiling under Win7 x64 is ok after modification of configure.ac

Code:

elif test "x$AMDAPPSDKROOT" != x; then
	OPENCL_FLAGS="-I$AMDAPPSDKROOT/include $OPENCL_FLAGS"
	OPENCL_LIBS="-L$AMDAPPSDKROOT/lib/$ARCH_DIR $OPENCL_LIBS"

this code was commented and I have no error
What do you say about that?

[-ck]

Code:

[2012-10-09 15:10:46] Rejected ed5dd272 Diff 1 MM 4 pool 0 (lowdifficulty)
 [2012-10-09 15:10:46] Rejected 1c494208 Diff 1 MM 2 pool 0 (lowdifficulty)
 [2012-10-09 15:10:48] Rejected c1b3226d Diff 1 MM 3 pool 0 (lowdifficulty)
 [2012-10-09 15:10:48] Rejected 25398ba3 Diff 1 MM 8 pool 0 (lowdifficulty)
 [2012-10-09 15:10:48] Rejected 1507a8f3 Diff 1 MM 3 pool 0 (lowdifficulty)
 [2012-10-09 15:10:48] Pool 0 rejected 11 sequential shares, disabling!
 [2012-10-09 15:10:48] Switching to stratum+tcp://50.31.149.59:10332
 [2012-10-09 15:10:48] Rejected 65f05b02 Diff 1 MM 2 pool 0 (lowdifficulty)
 [2012-10-09 15:10:48] Rejected 454e85fe Diff 1 MM 10 pool 0 (lowdifficulty)
 [2012-10-09 15:10:49] Rejected e3379b73 Diff 1 MM 6 pool 0 (lowdifficulty)
 [2012-10-09 15:10:49] Rejected 5ea8c46e Diff 1 MM 0 pool 0 (lowdifficulty)
 [2012-10-09 15:10:50] Rejected 8bc9d1a6 Diff 1 MM 7 pool 0 (lowdifficulty)
 [2012-10-09 15:10:50] Rejected a6f05450 Diff 1 MM 1 pool 0 (lowdifficulty)
 [2012-10-09 15:10:50] Rejected e447138f Diff 1 MM 10 pool 0 (lowdifficulty)
 [2012-10-09 15:10:52] Rejected df3e89a8 Diff 1 MM 10 pool 0 (lowdifficulty)
 [2012-10-09 15:10:52] Rejected 0c93beef Diff 1 MM 1 pool 1 (lowdifficulty)
 [2012-10-09 15:10:52] Stratum from pool 1 requested work restart
 [2012-10-09 15:10:53] Rejected 0ba592a1 Diff 1 MM 0 pool 1 (lowdifficulty)
 [2012-10-09 15:10:53] Rejected 5cedef55 Diff 1 MM 11 pool 1 (lowdifficulty)
 [2012-10-09 15:10:54] Rejected 29fdaac6 Diff 1 MM 2 pool 1 (lowdifficulty)
 [2012-10-09 15:10:54] Rejected b41da195 Diff 1 MM 0 pool 1 (lowdifficulty)
 [2012-10-09 15:10:54] Rejected 2d612681 Diff 1 MM 2 pool 1 (lowdifficulty)
 [2012-10-09 15:10:55] Rejected 10b690af Diff 1 MM 1 pool 1 (lowdifficulty)
 [2012-10-09 15:10:56] Rejected ca76b883 Diff 1 MM 11 pool 1 (lowdifficulty)
 [2012-10-09 15:10:56] Rejected 7d0f83d0 Diff 1 MM 5 pool 1 (lowdifficulty)
 [2012-10-09 15:10:57] Rejected ff00f1aa Diff 1 MM 8 pool 1 (lowdifficulty)
 [2012-10-09 15:10:57] Rejected 79b66986 Diff 1 MM 6 pool 1 (lowdifficulty)
 [2012-10-09 15:10:57] Pool 1 rejected 11 sequential shares, disabling!
 [2012-10-09 15:10:57] Switching to http://pool.50btc.com:8332
 [2012-10-09 15:10:57] Long-polling activated for http://pool2.50btc.com:8331/LP

I am using 2.8.1 with an own Driver for my own Mining Hardware. With Stratum i am not able to connect to BTCGuild. My Hardware generates 12GH/sec. Also switching to an other Username on the pool doesn't help. Seems that my Diff is not increasing.
Any Ideas. Going now back to 2.7.5.

That's interesting... Think about it.

[-ck]

I'm running 2.8.1 now. It seems to me that stratum+tcp pools that fail once are marked as dead and never will become alive again.

Code:

 cgminer version 2.8.1 - Started: [2012-10-09 22:36:17]
--------------------------------------------------------------------------------
 (5s):11.3 (avg):11.1 Mh/s | Q:3376  A:158  R:6  HW:0  E:5%  U:0.1/m
 TQ: 0  ST: 3  SS: 1  DW: 575  NB: 109  LW: 5813  GF: 5  RF: 1  WU: 0.1
 Connected to http://mining.eligius.st:8337 with LP as user <user>
 Block: 000003b4be07550c78f0b88a71d20b77...  Started: [17:32:35]
--------------------------------------------------------------------------------
 [P]ool management [G]PU management [S]ettings [D]isplay options [Q]uit
 GPU 0:  71.0C         |  11.2/ 11.1Mh/s | A:158 R:6 HW:0 U:0.14/m I: 9
--------------------------------------------------------------------------------

0: Enabled Dead Priority 0: api-stratum.bitcoin.cz  User:<user>
1: Enabled Dead Priority 1: stratum.btcguild.com  User:<user>
2: Enabled Alive Priority 2: http://mining.eligius.st:8337  User:<user>

Current pool management strategy: Failover
[F]ailover only disabled
[A]dd pool [R]emove pool [D]isable pool [E]nable pool
[C]hange management strategy [S]witch pool [I]nformation
Or press any other key to continue

When I stop cgminer and start it again, the first stratum pool in my list is alive again. The second stratum pool in the list is always dead.

Code:

0: Enabled Alive Priority 0: api-stratum.bitcoin.cz  User:<user>
1: Enabled Dead Priority 1: stratum.btcguild.com  User:<user>
2: Enabled Alive Priority 2: http://mining.eligius.st:8337  User:<user>

Yep, could be a bug. Investigating to see why that would be the case because it's meant to try reconnecting regularly.

[-ck]

I have problem with mining litecoins on some my rigs.
My 6 rigs mining very great.

For example:

GPU: 6870, 6870, 6770, 6770
Mobo: Asrock 890 FX Deluxe 5
RAM: 2 Gb
OS: Win7 64
Drivers: 11.12 with OCL libs from 11.11 (for mining bitcoins when it more profitable)

cgminer.cmd (I use same copies of cmd's on all my rigs and it works very well)
cgminer --scrypt --worksize 256 --shaders 1280 --lookup-gap 2 -g 1 --thread-concurrency 8192 --intensity 17 -o http://ltc.xurious.com:9332 -u user -p pass

Screenshot (the picture is clickable):
Xocтинг фoтoгpaфий


But there is one problem rig:

GPU: 6870, 6770
Mobo: Asus P5KPL AM SE
RAM: 1 Gb
OS: Win7 64
Drivers: 11.12 with OCL libs from 11.11

This rig mining bitcoins without any problems (I use phoenix 2.7.5).

But there are problems with mining litecoins. I tried also reaper (it works better on my rig with 7970) but not good too.

When I start cgminer.cmd it does not work:

Xocтинг фoтoгpaфий


If I change cgminer.cmd to
cgminer --scrypt --worksize 256 --shaders 1280 --lookup-gap 2 -g 1 --thread-concurrency 2048 --intensity 12 -o http://ltc.xurious.com:9332 -u user -p pass
it work, but hashrate is very very low.

If I up --thread-concurrency, it does not work.

If I up --intensity, it makes HW and not makes accepted shares:

Xocтинг фoтoгpaфий


I tried versions 2.7.4, 2.7.5, 2.7.6 and 2.8.1.

Help me, please.
While my GPU can't mining litecoins I am very unhappy.
Thank you.

System ram is required for litecoin mining as well. Your 2nd machine only has 1GB ram.

[-ck]

Last time this happened it was a packaging error on my part. I'll reupload shortly. I've reuploaded it.

ckolivas I've just downloaded the last zipped source from your git but the problem is

Code:

 OpenCL...............: NOT FOUND. GPU mining support DISABLED

That's a different one and a problem with your installation lacking the AMD APP SDK, or you lack including the directories (with -I) you have the sdk installed into.

ckolivas
Compiling under Win7 x64 is ok after modification of configure.ac

Code:

elif test "x$AMDAPPSDKROOT" != x; then
	OPENCL_FLAGS="-I$AMDAPPSDKROOT/include $OPENCL_FLAGS"
	OPENCL_LIBS="-L$AMDAPPSDKROOT/lib/$ARCH_DIR $OPENCL_LIBS"

this code was commented and I have no error
What do you say about that?

What I say is it works for me. From git you usually need ./autogen.sh first. Not sure on a zipball from git, might be the same. Try a source tarball from my server instead of from git.

[Maniac]

I have problem with mining litecoins on some my rigs.
My 6 rigs mining very great.

For example:

GPU: 6870, 6870, 6770, 6770
Mobo: Asrock 890 FX Deluxe 5
RAM: 2 Gb
OS: Win7 64
Drivers: 11.12 with OCL libs from 11.11 (for mining bitcoins when it more profitable)

cgminer.cmd (I use same copies of cmd's on all my rigs and it works very well)
cgminer --scrypt --worksize 256 --shaders 1280 --lookup-gap 2 -g 1 --thread-concurrency 8192 --intensity 17 -o http://ltc.xurious.com:9332 -u user -p pass

Screenshot (the picture is clickable):
Xocтинг фoтoгpaфий


But there is one problem rig:

GPU: 6870, 6770
Mobo: Asus P5KPL AM SE
RAM: 1 Gb
OS: Win7 64
Drivers: 11.12 with OCL libs from 11.11

This rig mining bitcoins without any problems (I use phoenix 2.7.5).

But there are problems with mining litecoins. I tried also reaper (it works better on my rig with 7970) but not good too.

When I start cgminer.cmd it does not work:

Xocтинг фoтoгpaфий


If I change cgminer.cmd to
cgminer --scrypt --worksize 256 --shaders 1280 --lookup-gap 2 -g 1 --thread-concurrency 2048 --intensity 12 -o http://ltc.xurious.com:9332 -u user -p pass
it work, but hashrate is very very low.

If I up --thread-concurrency, it does not work.

If I up --intensity, it makes HW and not makes accepted shares:

Xocтинг фoтoгpaфий


I tried versions 2.7.4, 2.7.5, 2.7.6 and 2.8.1.

Help me, please.
While my GPU can't mining litecoins I am very unhappy.
Thank you.

System ram is required for litecoin mining as well. Your 2nd machine only has 1GB ram.

Is 2 Gb RAM enough and good and not any problem with rigs that having from 2 to 5 GPU such as 5xxx, 6xxx, 7xxx ? (litecoin mining)

[-ck]

For me, whatever changes happened to dynamic in 2.7.6 have made it work poorly again. It is back to being really unresponsive to lowering when I am using the gpu for other things. It will lower one intensity or even stay the same as when I am not using the gpu for something else. I am on Windows 7 with two 5870s. What specifically changed with the algorithm in 2.7.6?

(2.7.5 is running smooth, and responds quickly when other programs use the gpu, and all I have to do on that version is set the intensity to fixed then back to dynamic and I never get the negative intensity bug anymore. 2.7.5 is the first version since 2.1.2 that I can get high performance when not using the gpu for other things and still have really responsive backing off of intensity when I do).

I got rid of the long term history in dynamic intensity going into 2.7.6, as the long term history was occasionally getting a dud result and pegging intensity to some small value indefinitely. I guess I'll just have to keep reworking this till it works everywhere.

[rav3n_pl]

For me, whatever changes happened to dynamic in 2.7.6 have made it work poorly again. It is back to being really unresponsive to lowering when I am using the gpu for other things. It will lower one intensity or even stay the same as when I am not using the gpu for something else. I am on Windows 7 with two 5870s. What specifically changed with the algorithm in 2.7.6?

(2.7.5 is running smooth, and responds quickly when other programs use the gpu, and all I have to do on that version is set the intensity to fixed then back to dynamic and I never get the negative intensity bug anymore. 2.7.5 is the first version since 2.1.2 that I can get high performance when not using the gpu for other things and still have really responsive backing off of intensity when I do).

I got rid of the long term history in dynamic intensity going into 2.7.6, as the long term history was occasionally getting a dud result and pegging intensity to some small value indefinitely. I guess I'll just have to keep reworking this till it works everywhere.

Maybe change it to "manual auto"? Let user choose 2 values of I and delay - when PC is on idle and when is busy. Then change lower intensity instantly when detected user activity and change to higher intensity when there is no user input over given time.

[averwind]

Following is how I am using the new stratum version:

cgminer -o btcguild.com:8332 -u averwind -p x -I 9 -v 2 -w 128

I have 10miners and all of them had the same windows message this morning "cgminer has stopped working".

Edit: I don't know if this will help but one of the 10 miners had "low memory" warning telling me to restart so that programs will run fine again.

[AxelMi]

Code:

[2012-10-09 15:10:46] Rejected ed5dd272 Diff 1 MM 4 pool 0 (lowdifficulty)
 [2012-10-09 15:10:46] Rejected 1c494208 Diff 1 MM 2 pool 0 (lowdifficulty)
 [2012-10-09 15:10:48] Rejected c1b3226d Diff 1 MM 3 pool 0 (lowdifficulty)
 [2012-10-09 15:10:48] Rejected 25398ba3 Diff 1 MM 8 pool 0 (lowdifficulty)
 [2012-10-09 15:10:48] Rejected 1507a8f3 Diff 1 MM 3 pool 0 (lowdifficulty)
 [2012-10-09 15:10:48] Pool 0 rejected 11 sequential shares, disabling!
 [2012-10-09 15:10:48] Switching to stratum+tcp://50.31.149.59:10332
 [2012-10-09 15:10:48] Rejected 65f05b02 Diff 1 MM 2 pool 0 (lowdifficulty)
 [2012-10-09 15:10:48] Rejected 454e85fe Diff 1 MM 10 pool 0 (lowdifficulty)
 [2012-10-09 15:10:49] Rejected e3379b73 Diff 1 MM 6 pool 0 (lowdifficulty)
 [2012-10-09 15:10:49] Rejected 5ea8c46e Diff 1 MM 0 pool 0 (lowdifficulty)
 [2012-10-09 15:10:50] Rejected 8bc9d1a6 Diff 1 MM 7 pool 0 (lowdifficulty)
 [2012-10-09 15:10:50] Rejected a6f05450 Diff 1 MM 1 pool 0 (lowdifficulty)
 [2012-10-09 15:10:50] Rejected e447138f Diff 1 MM 10 pool 0 (lowdifficulty)
 [2012-10-09 15:10:52] Rejected df3e89a8 Diff 1 MM 10 pool 0 (lowdifficulty)
 [2012-10-09 15:10:52] Rejected 0c93beef Diff 1 MM 1 pool 1 (lowdifficulty)
 [2012-10-09 15:10:52] Stratum from pool 1 requested work restart
 [2012-10-09 15:10:53] Rejected 0ba592a1 Diff 1 MM 0 pool 1 (lowdifficulty)
 [2012-10-09 15:10:53] Rejected 5cedef55 Diff 1 MM 11 pool 1 (lowdifficulty)
 [2012-10-09 15:10:54] Rejected 29fdaac6 Diff 1 MM 2 pool 1 (lowdifficulty)
 [2012-10-09 15:10:54] Rejected b41da195 Diff 1 MM 0 pool 1 (lowdifficulty)
 [2012-10-09 15:10:54] Rejected 2d612681 Diff 1 MM 2 pool 1 (lowdifficulty)
 [2012-10-09 15:10:55] Rejected 10b690af Diff 1 MM 1 pool 1 (lowdifficulty)
 [2012-10-09 15:10:56] Rejected ca76b883 Diff 1 MM 11 pool 1 (lowdifficulty)
 [2012-10-09 15:10:56] Rejected 7d0f83d0 Diff 1 MM 5 pool 1 (lowdifficulty)
 [2012-10-09 15:10:57] Rejected ff00f1aa Diff 1 MM 8 pool 1 (lowdifficulty)
 [2012-10-09 15:10:57] Rejected 79b66986 Diff 1 MM 6 pool 1 (lowdifficulty)
 [2012-10-09 15:10:57] Pool 1 rejected 11 sequential shares, disabling!
 [2012-10-09 15:10:57] Switching to http://pool.50btc.com:8332
 [2012-10-09 15:10:57] Long-polling activated for http://pool2.50btc.com:8331/LP

I am using 2.8.1 with an own Driver for my own Mining Hardware. With Stratum i am not able to connect to BTCGuild. My Hardware generates 12GH/sec. Also switching to an other Username on the pool doesn't help. Seems that my Diff is not increasing.
Any Ideas. Going now back to 2.7.5.

That's interesting... Think about it.

Must there a change in the driver for the stratum mining ?
with 2.7.5 i am using exactly the same driver with an external stratum pool and this combination works.

With 2.8.1 mining on a none stratum pool works.