Sorry for the late reply. I tried to disable GPU 12 and the miner works with GPUs 1-11. Then I tried to disable GPU9 and re-enable GPU 12 and the miner also works with GPU12 now working and GPU9 idle. I swapped the cards a bit too just to rule out hardware.

It appears only 11 GPUs can run at any given time. So this confirms it is not a GPU hardware problem.

I raised the VRAM to min 40GB and max 56GB and all 12 GPUs were humming along just fine. Thank you PhoenixMiner devs for the tip.

Yes, it is a barebones install. And I'm just wondering why it is happening now after many months of no issues with the miner.

2018.07.07:00:06:20.008: GPU12 GPU12: Using new optimized OpenCL kernels (device name 'Ellesmere')
2018.07.07:00:06:20.008: GPU12 GPU12: Allocating DAG (2.55) GB; good for epoch up to #199
2018.07.07:00:06:20.008: GPU12 GPU12: Allocating light cache buffer (40.9) MB; good for epoch up to #199
2018.07.07:00:06:20.034: GPU7 GPU7: DAG  31%
2018.07.07:00:06:20.207: GPU12 GPU12: Generating DAG for epoch #197
2018.07.07:00:06:20.325: GPU12 GPU12: clEnqueueNDRangeKernel (-4)
2018.07.07:00:06:20.358: GPU3 GPU3: DAG  69%
2018.07.07:00:06:20.381: GPU8 GPU8: DAG  31%
2018.07.07:00:06:20.514: eths Eth: Received: {"id":0,"jsonrpc":"2.0","result":["0x7706e461a7a11447870c2d2d1e31c32782b4a1460783687426746bffaf63346a","0x0ba3f65a466961c3edca9c346b0309ece42b254e0d0868b5f5163dfd9c9a3512","0x0112e0be826d694b2e62d01511f12a6061fbaec8bc02357593e70e52ba","0x5a47c8"]}
2018.07.07:00:06:20.514: eths Eth: New job #7706e461 from ssl://asia1.ethermine.org:5555; diff: 4000MH
2018.07.07:00:06:20.524: GPU12 GPU12: Starting up... (0)
2018.07.07:00:06:20.584: GPU12 GPU12: Using new optimized OpenCL kernels (device name 'Ellesmere')
2018.07.07:00:06:20.584: GPU12 GPU12: Allocating DAG (2.55) GB; good for epoch up to #199
2018.07.07:00:06:20.584: GPU12 GPU12: Allocating light cache buffer (40.9) MB; good for epoch up to #199
2018.07.07:00:06:20.728: GPU9 GPU9: DAG  31%
2018.07.07:00:06:20.784: GPU12 GPU12: Generating DAG for epoch #197
2018.07.07:00:06:20.846: GPU4 GPU4: DAG  63%
2018.07.07:00:06:20.886: GPU12 GPU12: clEnqueueNDRangeKernel (-4)
2018.07.07:00:06:21.067: eths Eth: Received: {"id":0,"jsonrpc":"2.0","result":["0xe195f9568ba69b30c01e7304266cac3f688d27559cc5f96d21001bdd71cd60ce","0x0ba3f65a466961c3edca9c346b0309ece42b254e0d0868b5f5163dfd9c9a3512","0x0112e0be826d694b2e62d01511f12a6061fbaec8bc02357593e70e52ba","0x5a47c8"]}
2018.07.07:00:06:21.067: eths Eth: New job #e195f956 from ssl://asia1.ethermine.org:5555; diff: 4000MH
2018.07.07:00:06:21.068: GPU10 GPU10: DAG  31%
2018.07.07:00:06:21.081: GPU5 GPU5: DAG  69%
2018.07.07:00:06:21.083: GPU12 GPU12: Starting up... (0)
2018.07.07:00:06:21.131: GPU12 GPU12: Using new optimized OpenCL kernels (device name 'Ellesmere')
2018.07.07:00:06:21.131: GPU12 GPU12: Allocating DAG (2.55) GB; good for epoch up to #199
2018.07.07:00:06:21.131: GPU12 GPU12: Allocating light cache buffer (40.9) MB; good for epoch up to #199
2018.07.07:00:06:21.197: wdog Thread(s) not responding. Restarting.
2018.07.07:00:06:21.330: GPU12 GPU12: Generating DAG for epoch #197
2018.07.07:00:06:21.396: GPU1 GPU1: DAG  94%
2018.07.07:00:06:21.407: GPU6 GPU6: DAG  69%
2018.07.07:00:06:21.422: GPU12 GPU12: clEnqueueNDRangeKernel (-4)

Lately I am getting a clEnqueueNDRange(-4) error on GPU 12. I only have 12 Sapphire RX570 GPUs attached to my rig.

My rig has been humming without any errors for many months. This just happened lately like since 2 weeks back. Any ideas how to solve this?

My virtual memory is already set to min 24000 and max 36000

I would like to ask if anyone is experiencing a larger percentage of stale shares lately?  My effective hashrate has dropped and stale shares at around 7%. I'm on ethermine pool mining ETH only.

My setup:
12 pcs of Sapphire Nitro+ RX570 8GB with custom memshift BIOS
GPU Clock at 1150MHz 800mV
Memory Clock at 2190MHz 850mV
PhoenixMiner 2.7a

Hi again,

I would like to understand further the lines of text printed on the console while the miner application is running.
Could you help me understand:

1. How to find out which GPUs are idle (waiting for job) and which GPUs are busy solving an algorithm?
2. How to find out how long it took to finish a share? and are shares solved by 1 GPU only or which GPUs helped to complete the share?
3. How to find out when a solution was submitted?
4. What is difference between "New job found... from " and "ETH share found"?

Let me know if these are details found on console of the app, or such debug strings can be printed by adding a parameter to the script, or such details are unavailable or do not exist.

Reason for asking this is that we could be too caught up with hashrates (processing power) and yet forget that idle GPUs (due to absence of a job or difficulty finding a share) affect performance too. No point overclocking GPUs only to be stuck waiting like a Ferrari stuck in traffic.

Thank you in advance.

Thank you for your reply. I also have no idea if it would so I had to ask just in case you would happen to know if it does improve getting shares.

My max hashrates are better with your miner than with Claymore's but I noticed that my effective hashrates are not so consistent, thus bringing down my average hashrates. I've been using your miner for just a day and noticed this. Not sure if it's related to that bug of GPU changing voltages during devfee mining. I didn't notice that but I saw someone post about it a few posts earlier.

Hi,

Thank you for making this miner.

I would like to know if your miner supports multiple instances. I have 12 cards and would want 2 instances of your miner running simultaneously with 6 cards accessible for each instance. Reason for doing this is to increase probability of getting shares.

Could you comment if this is possible, how to achieve it and if it will yield the benefits I stated?

Thank you and more power to you and your team.

John