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I am using an FPGA to mine bitcoins in a pool, as you can see below I am not really very successful:

[1 accepted, 48 failed, 148.90 +/- 21.27 Mhash/s]

It is running at 150 MhZ but I only have 1 accepted share out of 49. I guess this quota does not look to healhty. Anyone an idea what could be wrong?

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Is this a p2pool? Or perhaps a mining pool with a non-standard share difficulty? – David Schwartz Nov 24 '12 at 0:07
Which miner software and version? And is the pool using variable difficulty ("var diff") ? – Dr.Haribo Nov 24 '12 at 10:17
I am using this pool here: host = "" – Patrick Nov 26 '12 at 9:43
I am not sure what it means to use var diff, where can I find this out? – Patrick Nov 26 '12 at 9:44

Give me the make of the FPGA and the name of FPGA binary you are using.

It could well be that you are over-clocking the FPGA too far, due to the way that many of these cores are designed, there is a race condition, where the "success" flag, gets out of sync with the "nonce".

Basically the FPGA flags the "hit", but by the time it gets to copying the "nonce", it has changed...... and so fails.

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