Skip to content


Subversion checkout URL

You can clone with HTTPS or Subversion.

Download ZIP
ASIC and FPGA miner in c for bitcoin
tag: v2.2.0

Fetching latest commit…

Cannot retrieve the latest commit at this time

Failed to load latest commit information.


This is a multi-threaded multi-pool GPU, FPGA and CPU miner with ATI GPU
monitoring, (over)clocking and fanspeed support for bitcoin and derivative
coins. Do not use on multiple block chains at the same time!

This code is provided entirely free of charge by the programmer in his spare
time so donations would be greatly appreciated. Please consider using the
--donation feature or donate directly to the address below.

Con Kolivas <>



Support thread:

IRC Channel:


License: GPLv2.  See COPYING for details.


	curl dev library
	curses dev library
	(libncurses5-dev or libpdcurses on WIN32)
	(jansson is included in-tree and not necessary)
	yasm 1.0.1+
	(yasm is optional, gives assembly routines for CPU mining)
	(This sdk is mandatory for GPU mining)
	(This sdk is mandatory for ATI GPU monitoring & clocking)

CGMiner specific configuration options:
	--enable-cpumining      Build with cpu mining support(default disabled)
	--disable-opencl        Override detection and disable building with opencl
	--disable-adl           Override detection and disable building with adl
	--enable-bitforce       Compile support for BitForce FPGAs(default disabled)

Basic *nix build instructions:
	To build with GPU mining support:
	Install AMD APP sdk, ideal version (see FAQ!) - no official place to
	install it so just keep track of where it is if you're not installing
	the include files and library files into the system directory.
	(Do NOT install the ati amd sdk if you are on nvidia.)
	To build with GPU monitoring & clocking support:
	Extract the AMD ADL SDK, latest version - there is also no official
	place for these files. Copy all the *.h files in the "include"
	directory into cgminer's ADL_SDK directory.

The easiest way to install the ATI AMD SPP sdk on linux is to actually put it
into a system location. Then building will be simpler. Download the correct
version for either 32 bit or 64 bit from here:

This will give you a file with a name like AMD-APP-SDK-v2.4-lnx64.tgz


sudo su
cd /opt
tar xf /path/to/AMD-APP-SDK-v2.4-lnx64.tgz
cd /
tar xf /opt/AMD-APP-SDK-v2.4-lnx64/icd-registration.tgz
ln -s /opt/AMD-APP-SDK-v2.4-lnx64/include/CL /usr/include
ln -s /opt/AMD-APP-SDK-v2.4-lnx64/lib/x86_64/* /usr/lib/

If you are on 32 bit, x86_64 in the 2nd last line should be x86

	To actually build:

	./	# only needed if building from git repo
	CFLAGS="-O2 -Wall -march=native" ./configure
	or if you haven't installed the ati files in system locations:
	CFLAGS="-O2 -Wall -march=native -I<path to AMD APP include>" LDFLAGS="-L<path to AMD APP lib/x86_64> ./configure
	If it finds the opencl files it will inform you with
	"OpenCL: FOUND. GPU mining support enabled."

Basic WIN32 build instructions (LIKELY OUTDATED INFO. requires mingw32):
	./	# only needed if building from git repo
	rm -f mingw32-config.cache
	MINGW32_CFLAGS="-O2 -Wall -msse2" mingw32-configure
Native WIN32 build instructions (on mingw32, on windows):
	Install the Microsoft platform SDK
	Install AMD APP sdk, (if you want GPU mining)
	Install AMD ADL sdk, (if you want GPU monitoring)
	(Do NOT install the ati amd sdk if you are on nvidia)
	Install mingw32
	Install libcurl, copy libcurl.m4 into /mingw/share/aclocal
	Install pkg-config, copy pkg.m4 into /mingw/share/aclocal
	autoreconf -fvi
	CFLAGS="-O2 -msse2" ./configure


Usage instructions:  Run "cgminer --help" to see options:

Usage: . [-atDdGCgIKklmpPQqrRsTouvwOchnV] 
Options for both config file and command line:
--api-description   Description placed in the API status header (default: cgminer version)
--api-listen        Listen for API requests (default: disabled)
--api-network       Allow API (if enabled) to listen on/for any address (default: only
--api-port          Port number of miner API (default: 4028)
--auto-fan          Automatically adjust all GPU fan speeds to maintain a target temperature
--auto-gpu          Automatically adjust all GPU engine clock speeds to maintain a target temperature
--debug|-D          Enable debug output
--donation <arg>    Set donation percentage to cgminer author (0.0 - 99.9) (default: 0.0)
--expiry|-E <arg>   Upper bound on how many seconds after getting work we consider a share from it stale (default: 120)
--failover-only     Don't leak work to backup pools when primary pool is lagging
--load-balance      Change multipool strategy from failover to even load balance
--log|-l <arg>      Interval in seconds between log output (default: 5)
--monitor|-m <arg>  Use custom pipe cmd for output messages
--net-delay         Impose small delays in networking to not overload slow routers
--no-longpoll       Disable X-Long-Polling support
--pass|-p <arg>     Password for bitcoin JSON-RPC server
--per-device-stats  Force verbose mode and output per-device statistics
--protocol-dump|-P  Verbose dump of protocol-level activities
--queue|-Q <arg>    Minimum number of work items to have queued (0 - 10) (default: 1)
--quiet|-q          Disable logging output, display status and errors
--real-quiet        Disable all output
--remove-disabled   Remove disabled devices entirely, as if they didn't exist
--retries|-r <arg>  Number of times to retry before giving up, if JSON-RPC call fails (-1 means never) (default: -1)
--retry-pause|-R <arg> Number of seconds to pause, between retries (default: 5)
--rotate <arg>      Change multipool strategy from failover to regularly rotate at N minutes (default: 0)
--round-robin       Change multipool strategy from failover to round robin on failure
--scan-time|-s <arg> Upper bound on time spent scanning current work, in seconds (default: 60)
--sched-start <arg> Set a time of day in HH:MM to start mining (a once off without a stop time)
--sched-stop <arg>  Set a time of day in HH:MM to stop mining (will quit without a start time)
--shares <arg>      Quit after mining N shares (default: unlimited)
--socks-proxy <arg> Set socks4 proxy (host:port)
--submit-stale      Submit shares even if they would normally be considered stale
--syslog            Use system log for output messages (default: standard error)
--text-only|-T      Disable ncurses formatted screen output
--url|-o <arg>      URL for bitcoin JSON-RPC server
--user|-u <arg>     Username for bitcoin JSON-RPC server
--verbose           Log verbose output to stderr as well as status output
--userpass|-O <arg> Username:Password pair for bitcoin JSON-RPC server
Options for command line only:
--config|-c <arg>   Load a JSON-format configuration file
See example.conf for an example configuration.
--help|-h           Print this message
--version|-V        Display version and exit

GPU only options:

--auto-fan          Automatically adjust all GPU fan speeds to maintain a target temperature
--auto-gpu          Automatically adjust all GPU engine clock speeds to maintain a target temperature
--device|-d <arg>   Select device to use, (Use repeat -d for multiple devices, default: all)
--disable-gpu|-G    Disable GPU mining even if suitable devices exist
--gpu-threads|-g <arg> Number of threads per GPU (1 - 10) (default: 2)
--gpu-engine <arg>  GPU engine (over)clock range in Mhz - one value, range and/or comma separated list (e.g. 850-900,900,750-850)
--gpu-fan <arg>     GPU fan percentage range - one value, range and/or comma separated list (e.g. 25-85,85,65)
--gpu-memclock <arg> Set the GPU memory (over)clock in Mhz - one value for all or separate by commas for per card.
--gpu-memdiff <arg> Set a fixed difference in clock speed between the GPU and memory in auto-gpu mode
--gpu-powertune <arg> Set the GPU powertune percentage - one value for all or separate by commas for per card.
--gpu-vddc <arg>    Set the GPU voltage in Volts - one value for all or separate by commas for per card.
--intensity|-I <arg> Intensity of GPU scanning (d or -10 -> 10, default: d to maintain desktop interactivity)
--kernel-path|-K <arg> Specify a path to where the kernel .cl files are (default: "/usr/local/bin")
--kernel|-k <arg>   Select kernel to use (poclbm or phatk - default: auto)
--no-restart        Do not attempt to restart GPUs that hang
--temp-cutoff <arg> Temperature where a GPU device will be automatically disabled, one value or comma separated list (default: 95)
--temp-hysteresis <arg> Set how much the temperature can fluctuate outside limits when automanaging speeds (default: 3)
--temp-overheat <arg> Overheat temperature when automatically managing fan and GPU speeds (default: 85)
--temp-target <arg> Target temperature when automatically managing fan and GPU speeds (default: 75)
--vectors|-v <arg>  Override detected optimal vector width (1, 2 or 4)
--worksize|-w <arg> Override detected optimal worksize (default: 0)
--ndevs|-n          Enumerate number of detected GPUs and exit

BitForce only options:

--scan-serial|-S <arg> Serial port to probe for BitForce device

CPU only options:

--algo|-a <arg>     Specify sha256 implementation for CPU mining:
        auto            Benchmark at startup and pick fastest algorithm
        c               Linux kernel sha256, implemented in C
        4way            tcatm's 4-way SSE2 implementation
        via             VIA padlock implementation
        cryptopp        Crypto++ C/C++ implementation
        sse2_64         SSE2 64 bit implementation for x86_64 machines
        sse4_64         SSE4.1 64 bit implementation for x86_64 machines (default: sse2_64)
--cpu-threads|-t <arg> Number of miner CPU threads (default: 4)
--enable-cpu|-C     Enable CPU mining with other mining (default: no CPU mining if other devices exist)



After saving configuration from the menu, you do not need to give cgminer any
arguments and it will load your configuration.

Single pool, regular desktop:

cgminer -o http://pool:port -u username -p password

Single pool, dedicated miner:

cgminer -o http://pool:port -u username -p password -I 9

Single pool, first card regular desktop, 3 other dedicated cards:

cgminer -o http://pool:port -u username -p password -I d,9,9,9

Multiple pool, dedicated miner:

cgminer -o http://pool1:port -u pool1username -p pool1password -o http://pool2:port -u pool2usernmae -p pool2password -I 9

Add overclocking settings, GPU and fan control for all cards:

cgminer -o http://pool:port -u username -p password -I 9 --auto-fan --auto-gpu --gpu-engine 750-950 --gpu-memclock 300

Add overclocking settings, GPU and fan control with different engine settings for 4 cards:

cgminer -o http://pool:port -u username -p password -I 9 --auto-fan --auto-gpu --gpu-engine 750-950,945,700-930,960 --gpu-memclock 300


On Linux you virtually always need to export your display settings before
starting to get all the cards recognised and/or temperature+clocking working:

export DISPLAY=:0



The following options are available while running with a single keypress:

[P]ool management [G]PU management [S]ettings [D]isplay options [Q]uit

P gives you:

Current pool management strategy: Failover
[A]dd pool [R]emove pool [D]isable pool [E]nable pool
[C]hange management strategy [S]witch pool [I]nformation

S gives you:

[L]ongpoll: On
[Q]ueue: 1
[S]cantime: 60
[E]xpiry: 120
[R]etries: -1
[P]ause: 5
[W]rite config file

D gives you:

Toggle: [D]ebug [N]ormal [S]ilent [V]erbose [R]PC debug
[L]og interval [C]lear

Q quits the application.

G gives you something like:

GPU 0: [124.2 / 191.3 Mh/s] [Q:212  A:77  R:33  HW:0  E:36%  U:1.73/m]
Temp: 67.0 C
Fan Speed: 35% (2500 RPM)
Engine Clock: 960 MHz
Memory Clock: 480 Mhz
Vddc: 1.200 V
Activity: 93%
Powertune: 0%
Last initialised: [2011-09-06 12:03:56]
Thread 0: 62.4 Mh/s Enabled ALIVE
Thread 1: 60.2 Mh/s Enabled ALIVE

[E]nable [D]isable [R]estart GPU [C]hange settings
Or press any other key to continue

Also many issues and FAQs are covered in the forum thread
dedicated to this program,

The output line shows the following:
(5s):1713.6 (avg):1707.8 Mh/s | Q:301  A:729  R:8  HW:0  E:242%  U:22.53/m

Each column is as follows:
A 5 second exponentially decaying average hash rate
An all time average hash rate
The number of requested (Queued) work items from the pools
The number of Accepted shares
The number of Rejected shares
The number of HardWare errors
The Efficiency defined as number of shares returned / work item
The Utility defined as the number of shares / minute

 GPU 1: 73.5C 2551RPM | 427.3/443.0Mh/s | A:8 R:0 HW:0 U:4.39/m

Each column is as follows:
Temperature (if supported)
Fanspeed (if supported)
A 5 second exponentially decaying average hash rate
An all time average hash rate
The number of accepted shares
The number of rejected shares
The number of hardware erorrs
The utility defines as the number of shares / minute

The cgminer status line shows:
 TQ: 1  ST: 1  SS: 0  DW: 0  NB: 1  LW: 8  GF: 1  RF: 1

TQ is Total Queued work items.
ST is STaged work items (ready to use).
SS is Stale Shares discarded (detected and not submitted so don't count as rejects)
DW is Discarded Work items (work from block no longer valid to work on)
NB is New Blocks detected on the network
LW is Locally generated Work items
GF is Getwork Fail Occasions (server slow to provide work)
RF is Remote Fail occasions (server slow to accept work)

NOTE: Running intensities above 9 with current hardware is likely to only
diminish return performance even if the hash rate might appear better. A good
starting baseline intensity to try on dedicated miners is 9. Higher values are
there to cope with future improvements in hardware.


A number of different strategies for dealing with multipool setups are
available. Each has their advantages and disadvantages so multiple strategies
are available by user choice, as per the following list:

The default strategy is failover. This means that if you input a number of
pools, it will try to use them as a priority list, moving away from the 1st
to the 2nd, 2nd to 3rd and so on. If any of the earlier pools recover, it will
move back to the higher priority ones.

This strategy only moves from one pool to the next when the current one falls
idle and makes no attempt to move otherwise.

This strategy moves at user-defined intervals from one active pool to the next,
skipping pools that are idle.

This strategy sends work in equal amounts to all the pools specified. If any
pool falls idle, the rest will take up the slack keeping the miner busy.


cgminer will log to stderr if it detects stderr is being redirected to a file.
To enable logging simply add 2>logfile.txt to your command line and logfile.txt
will contain the logged output at the log level you specify (normal, verbose,
debug etc.)

In other words if you would normally use:
./cgminer -o xxx -u yyy -p zzz
if you use
./cgminer -o xxx -u yyy -p zzz 2>logfile.txt
it will log to a file called logfile.txt and otherwise work the same.

There is also the -m option on linux which will spawn a command of your choice
and pipe the output directly to that command.



The GPU monitoring, clocking and fanspeed control incorporated into cgminer
comes through use of the ATI Display Library. As such, it only supports ATI
GPUs. Even if ADL support is successfully built into cgminer, unless the card
and driver supports it, no GPU monitoring/settings will be available.

Cgminer supports initial setting of GPU engine clock speed, memory clock
speed, voltage, fanspeed, and the undocumented powertune feature of 69x0+ GPUs.
The setting passed to cgminer is used by all GPUs unless separate values are
specified. All settings can all be changed within the menu on the fly on a
per-GPU basis.

For example:
--gpu-engine 950 --gpu-memclock 825

will try to set all GPU engine clocks to 950 and all memory clocks to 825,
--gpu-engine 950,945,930,960 --gpu-memclock 300

will try to set the engine clock of card 0 to 950, 1 to 945, 2 to 930, 3 to
960 and all memory clocks to 300.

There are two "auto" modes in cgminer, --auto-fan and --auto-gpu. These can
be used independently of each other and are complementary. Both auto modes
are designed to safely change settings while trying to maintain a target
temperature. By default this is set to 75 degrees C but can be changed with:

--temp-target 80
Sets all cards' target temperature to 80 degrees.

--temp-target 75,85
Sets card 0 target temperature to 75, and card 1 to 85 degrees.

--auto-fan (implies 85% upper limit)
--gpu-fan 25-85,65 --auto-fan

Fan control in auto fan works off the theory that the minimum possible fan
required to maintain an optimal temperature will use less power, make less
noise, and prolong the life of the fan. In auto-fan mode, the fan speed is
limited to 85% if the temperature is below "overheat" intentionally, as
higher fanspeeds on GPUs do not produce signficantly more cooling, yet
significanly shorten the lifespan of the fans. If temperature reaches the
overheat value, fanspeed will still be increased to 100%. The overheat value
is set to 85 degrees by default and can be changed with:

--temp-overheat 75,85
Sets card 0 overheat threshold to 75 degrees and card 1 to 85.

--auto-gpu --gpu-engine 750-950
--auto-gpu --gpu-engine 750-950,945,700-930,960

GPU control in auto gpu tries to maintain as high a clock speed as possible
while not reaching overheat temperatures. As a lower clock speed limit,
the auto-gpu mode checks the GPU card's "normal" clock speed and will not go
below this unless you have manually set a lower speed in the range. Also,
unless a higher clock speed was specified at startup, it will not raise the
clockspeed. If the temperature climbs, fanspeed is adjusted and optimised
before GPU engine clockspeed is adjusted. If fan speed control is not available
or already optimal, then GPU clock speed is only decreased if it goes over
the target temperature by the hysteresis amount, which is set to 3 by default
and can be changed with:
If the temperature drops below the target temperature, and engine clock speed
is not at the highest level set at startup, cgminer will raise the clock speed.
If at any time you manually set an even higher clock speed successfully in
cgminer, it will record this value and use it as its new upper limit (and the
same for low clock speeds and lower limits). If the temperature goes over the
cutoff limit (95 degrees by default), cgminer will completely disable the GPU
from mining and it will not be re-enabled unless manually done so. The cutoff
temperature can be changed with:

--temp-cutoff 95,105
Sets card 0 cutoff temperature to 95 and card 1 to 105.

--gpu-memdiff -125
This setting will modify the memory speed whenever the GPU clock speed is
modified by --auto-gpu. In this example, it will set the memory speed to
be 125 Mhz lower than the GPU speed. This is useful for some cards like the
6970 which normally don't allow a bigger clock speed difference.

When setting values, it is important to realise that even though the driver
may report the value was changed successfully, and the new card power profile
information contains the values you set it to, that the card itself may
refuse to use those settings. As the performance profile changes dynamically,
querying the "current" value on the card can be wrong as well. So when changing
values in cgminer, after a pause of 1 second, it will report to you the current
values where you should check that your change has taken. An example is that
6970 reference cards will accept low memory values but refuse to actually run
those lower memory values unless they're within 125 of the engine clock speed.
In that scenario, they usually set their real speed back to their default.

Cgminer reports the so-called "safe" range of whatever it is you are modifying
when you ask to modify it on the fly. However, you can change settings to values
outside this range. Despite this, the card can easily refuse to accept your
changes, or worse, to accept your changes and then silently ignore them. So
there is absolutely to know how far to/from where/to it can set things safely or
otherwise, and there is nothing stopping you from at least trying to set them
outside this range. Being very conscious of these possible failures is why
cgminer will report back the current values for you to examine how exactly the
card has responded. Even within the reported range of accepted values by the
card, it is very easy to crash just about any card, so it cannot use those
values to determine what range to set. You have to provide something meaningful
manually for cgminer to work with through experimentation.

When cgminer starts up, it tries to read off the current profile information
for clock and fan speeds and stores these values. When quitting cgminer, it
will then try to restore the original values. Changing settings outside of
cgminer while it's running may be reset to the startup cgminer values when
cgminer shuts down because of this.



If you start cgminer with the "--api-listen" option, it will listen on a
simple TCP/IP socket for single string API requests from the same machine
running cgminer and reply with a string and then close the socket each time
Also, if you add the "--api-network" option, it will accept API requests
from any network attached computer.

The request can be either simple text or JSON.

If the request is JSON (starts with '{'), it will reply with a JSON formatted
response, otherwise it replies with text formatted as described further below.

The JSON request format required is '{"command":"CMD","parameter":"PARAM"}'
(though of course parameter is not required for all requests)
where "CMD" is from the "Request" column below and "PARAM" would be e.g.
the CPU/GPU number if required.

An example request in both formats:

The format of each reply (unless stated otherwise) is a STATUS section
followed by an optional detail section

The STATUS section is:


  STATUS=X Where X is one of:
   W - Warning
   I - Informational
   S - Success
   E - Error
   F - Fatal (code bug)

   Each unique reply has a unigue Code (See api.c - #define MSG_NNNNNN)

   Message matching the Code value N

   This defaults to the cgminer version but is the value of --api-description
   if it was specified at runtime.

The list of requests and replies are:

 Request       Reply Section  Details
 -------       -------------  -------
 version       VERSION        CGMiner=cgminer version
                              API=API version

 config        CONFIG         Some miner configuration information:
                              GPU Count=N, <- the number of GPUs
                              CPU Count=N, <- the number of CPUs
                              Pool Count=N, <- the number of Pools
                              ADL=X, <- Y or N if ADL is compiled in the code
                              ADL in use=X, <- Y or N if any GPU has ADL
                              Strategy=Name| <- the current pool strategy

 summary       SUMMARY        The status summary of the miner
                              e.g. Elapsed=NNN,Found Blocks=N,Getworks=N,...|

 pools         POOLS          The status of each pool
                              e.g. Pool=0,URL=,Status=Alive,...|

 devs          DEVS           Each available CPU and GPU with their details
                              e.g. GPU=0,Accepted=NN,MHS av=NNN,...,Intensity=D|
                              Will not report CPUs if CPU mining is disabled

 gpu|N         GPU            The details of a single GPU number N in the same
                              format and details as for DEVS

 cpu|N         CPU            The details of a single CPU number N in the same
                              format and details as for DEVS
                              This is only available if CPU mining is enabled
                              Use 'cpucount' or 'config' first to see if there are any

 gpucount      GPUS           Count=N| <- the number of GPUs

 cpucount      CPUS           Count=N| <- the number of CPUs
                              Always returns 0 if CPU mining is disabled

 switchpool|N  none           There is no reply section just the STATUS section
                              stating the results of switching pool N to the
                              highest priority (the pool is also enabled)
                              The Msg includes the pool URL

 gpuenable|N   none           There is no reply section just the STATUS section
                              stating the results of the enable request

 gpudisable|N  none           There is no reply section just the STATUS section
                              stating the results of the disable request

 gpurestart|N  none           There is no reply section just the STATUS section
                              stating the results of the restart request

 gpuintensity|N,I  none       There is no reply section just the STATUS section
                              stating the results of setting GPU N intensity to I

 gpumem|N,V    none           There is no reply section just the STATUS section
                              stating the results of setting GPU N memoryclock to V MHz

 gpuengine|N,V none           There is no reply section just the STATUS section
                              stating the results of setting GPU N clock to V MHz

 gpufan|N,V    none           There is no reply section just the STATUS section
                              stating the results of setting GPU N fan speed to V%

 gpuvddc|N,V   none           There is no reply section just the STATUS section
                              stating the results of setting GPU N vddc to V

 save|filename none           There is no reply section just the STATUS section
                              stating success or failure saving the cgminer config
                              to filename

 quit          none           There is no status section but just a single "BYE|"
                              reply before cgminer quits

When you enable, disable or restart a GPU, you will also get Thread messages in
the cgminer status window

Obviously, the JSON format is simply just the names as given before the '='
with the values after the '='

If you enable cgminer debug (-D or --debug) you will also get messages showing
details of the requests received and the replies

There are included 4 program examples for accessing the API:

api-example.php - a php script to access the API
  usAge: php api-example.php command
 by default it sends a 'summary' request to the miner at
 If you specify a command it will send that request instead
 You must modify the line "$socket = getsock('', 4028);" at the
 beginning of "function request($cmd)" to change where it looks for cgminer
 a java program to access the API (with source code)
  usAge is: java API command address port
 Any missing or blank parameters are replaced as if you entered:
  java API summary 4028

api-example.c - a 'C' program to access the API (with source code)
  usAge: api-example [command [ip/host [port]]]
 again, as above, missing or blank parameters are replaced as if you entered:
  api-example summary 4028

miner.php - an example web page to access the API
 This includes buttons to enable, disable and restart the GPUs and also to
 quit cgminer
 You must modify the 2 lines near the top to change where it looks for cgminer
  $miner = ''; # hostname or IP address
  $port = 4028;



Q: cgminer segfaults when I change my shell window size.
A: Older versions of libncurses have a bug to do with refreshing a window
after a size change. Upgrading to a new version of curses will fix it.

Q: Can I mine on servers from different networks (eg smartcoin and bitcoin) at
the same time?
A: No, cgminer keeps a database of the block it's working on to ensure it does
not work on stale blocks, and having different blocks from two networks would
make it invalidate the work from each other.

Q: Can I change the intensity settings individually for each GPU?
A: Yes, pass a list separated by commas such as -I d,4,9,9

Q: Can I put multiple pools in the config file?
A: Yes, check the example.conf file. Alternatively, set up everything either on
the command line or via the menu after startup and choose settings->write
config file and the file will be loaded one each startup.

Q: The build fails with gcc is unable to build a binary.
A: Remove the "-march=native" component of your CFLAGS as your version of gcc
does not support it.

Q: The CPU usage is high.
A: The ATI drivers after 11.6 have a bug that makes them consume 100% of one
CPU core unnecessarily so downgrade to 11.6. Binding cgminer to one CPU core on
windows can minimise it to 100% (instead of more than one core). Driver version
11.11 on linux and 11.12 on windows appear to have fixed this issue.

Q: Can you implement feature X?
A: I can, but time is limited, and people who donate are more likely to get
their feature requests implemented.

Q: My GPU hangs and I have to reboot it to get it going again?
A: The more aggressively the mining software uses your GPU, the less overclock
you will be able to run. You are more likely to hit your limits with cgminer
and you will find you may need to overclock your GPU less aggressively. The
software cannot be responsible and make your GPU hang directly. If you simply
cannot get it to ever stop hanging, try decreasing the intensity, and if even
that fails, try changing to the poclbm kernel with -k poclbm, though you will
sacrifice performance. cgminer is designed to try and safely restart GPUs as
much as possible, but NOT if that restart might actually crash the rest of the
GPUs mining, or even the machine. It tries to restart them with a separate
thread and if that separate thread dies, it gives up trying to restart any more

Q: Work keeps going to my backup pool even though my primary pool hasn't
A: Cgminer checks for conditions where the primary pool is lagging and will
pass some work to the backup servers under those conditions. The reason for
doing this is to try its absolute best to keep the GPUs working on something
useful and not risk idle periods. You can disable this behaviour with the
option --failover-only.

Q: Is this a virus?
A: Cgminer is being packaged with other trojan scripts and some antivirus
software is falsely accusing cgminer.exe as being the actual virus, rather
than whatever it is being packaged with. If you installed cgminer yourself,
then you do not have a virus on your computer. Complain to your antivirus
software company.

Q: How does the donation feature work and how does it affect my shares?
A: The donation feature is disabled by default and only does anything once
enabled. It queries the author's website for login credentials and contributes
up to a proportion of work to the author's account. While the overall
accepted/rejected rates will include this work, none of these will appear in
your own accounts. On exiting, the summary will tell you how many shares were
contributed to the author.

Q: Can you modify the display to include more of one thing in the output and
less of another, or can you change the quiet mode or can you add yet another
output mode?
A: Everyone will always have their own view of what's important to monitor.
The defaults are very sane and I have very little interest in changing this
any further.

Q: Can you change the autofan/autogpu to change speeds in a different manner?
A: The defaults are sane and safe. I'm not interested in changing them
further. The starting fan speed is set to 85% in auto-fan mode as a safety
precaution, but if a specific fan speed has been set, it will use that first
before adjusting automatically.

Q: The fanspeed starts at 85% with --auto-fan. Can I set it lower?
A: The initial fanspeed will always start at 85% unless you choose your own
value with --gpu-fan. In this case it will use the value you give it with
--gpu-fan as the first fanspeed.

Q: Why is my efficiency above/below 100%?
A: Efficiency simply means how many shares you return for the amount of work
you request. It does not correlate with efficient use of your hardware, and is
a measure of a combination of hardware speed, block luck, pool design and other

Q: What are the best parameters to pass for X pool/hardware/device.
A: Virtually always, the DEFAULT parameters give the best results. Most user
defined settings lead to worse performance. The ONLY thing most users should
need to set is the Intensity.

Q: What happened to CPU mining?
A: Being increasingly irrelevant for most users, and a maintenance issue, it is
no longer under active development and will not be supported unless someone
steps up to help maintain it. No binary builds supporting CPU mining will be
released but CPU mining can be built into cgminer when it is compiled.

Q: I upgraded my ATI driver/SDK/cgminer and my hashrate suddenly dropped!
A: The hashrate performance in cgminer is tied to the version of the ATI SDK
that is installed only for the very first time cgminer is run. This generates
binaries that are used by the GPU every time after that. Any upgrades to the
SDK after that time will have no effect on the binaries. However, if you
install a fresh version of cgminer, and have since upgraded your SDK, new
binaries will be built. It is known that the 2.6 ATI SDK has a huge hashrate
penalty on generating new binaries. It is recommended to not use this SDK at
this time.

Q: Which ATI SDK is the best for cgminer?
A: At the moment, versions 2.4 and 2.5 work the best. If you are forced to use
the 2.6 SDK, -v 1 -w 64 might help, along with not decreasing your memory clock

Q: ATI 79XX support?
A: Work in progress. Still needs a lot of work to get a good hashrate.

Q: GUI version?
A: No. The RPC interface makes it possible for someone else to write one


This code is provided entirely free of charge by the programmer in his spare
time so donations would be greatly appreciated. Please consider using the
--donation feature or donate directly to the address below.

Con Kolivas <>
Something went wrong with that request. Please try again.