PhoenixMiner 5.2e (release candidate) is ready with some fixes for AMD cards. You can download PhoenixMiner 5.2e from here (both Windows and Linux versions):
If you want to check the integrity of the downloaded file, please use the following hashes (you need the last file PhoenixMiner_NVRTC_Windows.zip only if you want to mine BCI with Nvdia cards under Windows):
The changes in this release (since 5.2d) include the following:
- Fixed some problems with using 8GB AMD cards
- Fixed some problems with 4GB AMD cards when mining ETH or ETC
- Fixed crash when using the AMD Windows beta blockchain drivers from 2017 (still not recommended to use these drivers)
- Added support for the latest AMD Windows 10 drivers 20.11.2
The changes of the previous beta (5.2d) since the last version (5.1c) are:
- AMD cards with more than 4 GB RAM will now work without issues until DAG epoch 450
- Added new -daglim parameter to allow a few more weeks of work for 4 GB AMD Polaris, Fiji, Tonga, and Baffin cards. It is automatically enabled for the 4GB cards if the DAG size approaches 4GB. You can also specify a concrete value for the maximum DAG size (example: -daglim 4000 will set max DAG size 4000 MB). Under Windows the default DAG limit is 4023, and under Linux it is 4064 for older drivers (before 19.50), and 4076 for the newer drivers.
- Added -rxboost parameter (also accessible via -vmr ) to boost the performance of GDDR5 based AMD cards (Polaris or earlier)
- Added experimental memory straps support for AMD Vega cards. Use the -straps command-line option to activate it (example: -straps 1 will activate the lowest strap level)
- The Nvidia memory timing (straps) option is improved and now is turned off during DAG generation to avoid any possible instability issues
- Added support for the AMD Linux drivers 20.20, and 20.30
- Added support for the latest AMD Linux drivers 20.40-1147286 (however they seem to have hardware control problems with some cards, so no need to upgrade for now)
- Many other small improvements and fixes
Here are some additional notes:
- The -daglim option works on Polaris (RX470, RX480, RX570, RX580, RX590), Baffin (RX560, RX550), Tonga, and Fiji cards. It limits the DAG size to MB to allow mining on 4 GB cards a few weeks after epoch 374 on Windows (or after 381 on Linux). The possible values are the exact DAG limit in MB, or 0 (turn off the DAG limit), or 1 (automatic DAG limit size, usually around 4023 MB under Windows; this is the default option). Note that the hashrate will drop significantly with each epoch after the DAG limit is in effect . If the hashrate drops too much (e.g. from 28 MH/s to just 2-3 MH/s, you need to use lower value, for example -daglim 3990
- (Windows) With PhoenixMiner 5.2e either remove the -daglim option entirely (it is set to auto by default), or set it to -daglim 4023 , which should work on all 470/480/570/580/590 cards with “good” drivers (see bellow)
- (Windows) If you cards doesn’t work with the default DAG limit of 4023 and require substantial decrease to 4006 or 3990, you need to update to one of the “good” AMD drivers for Windows: from 220.127.116.11 to 19.7.5 (inclusive), and from 19.12.2 to 20.11.1 (inclusive)
- (Linux) With PhoenixMiner 5.2e either remove the -daglim option entirely (it is set to auto by default), or set it to -daglim 4064 on older drivers (before 19.50), or -daglim 4076 on newer drivers.
- (Linux) When the -daglim option is in effect (i.e. if you are mining ETH or ETC with 4GB cards), the miner will restart on each new DAG epoch, and will force serial (one-by-one) generation of the DAG buffers. To allow more stable operation under these conditions, it is best to use -rmode 0 and to use a script to restart the miner when it exits. Two such scripts are provided with the miner: start_amd_4g_old_drv.sh for older drivers (before 19.50, note that when using -rmode 0, the -daglim for these older drivers can be increased to 4068), and start_amd_4g_new_drv.sh for newer drivers. Make sure to change the pools and the wallet in these scripts with your own before using them for mining.
- It is also important to use auto-tune (do not specify -gt values in the command line) because the optimal -gt value may change with each new epoch, and will definitely be different than before.
- The new -rxboost option sets the memory refresh rate on AMD cards (only those with GDDR5 memory). The possible values are: 0 - default values, 1 - predefined value that should work on most cards, 2 to 100 - increasingly aggressive settings from lowest to highest. You should start by specifying -rxboost 1 , then check the log file and find a message like this: “set VRAM refresh rate -rxboost 1 (equal to -vmr xx )” . Write down the xx value and then replace -rxboost 1 with -vmr xx (for example [ tt]-vmr 25[/tt] ). You can than try to increase the -vmr value until you start to see incorrect shares or some other instability (crashes, freezes, etc). If even the default value gives you incorrect shares or other problems, you should decrease it.
- Using -rxboost , -vmr , or -straps on AMD cards requires running as administrator (or as root under Linux), so you need to run PhoenixMiner as administrator for the VRAM timing options to work . Note that the -mt option will still work without running as administrator.
- The -rxboost option is only supported on GDDR5 cards (RX4xx/RX5xx or older).
- The VRAM timing options can be quite different between the GPUs, even when the GPUs are the same model. Therefore, you can (and probably should) specify the VRAM timing options separately for each GPU.
Please let us know if you have any problems or questions related to PhoenixMiner 5.2e.