eg. if your hash rate is 300GH/s and you have 2% errors and 1% rejected then 300-9 = 291GH/s
Thanks. Ok, where do I find errors? The rejects are .13%. Also, I'm not following your formula. Your example is 2% errors and 1% rejects (3%) subtracted from the hashrate (300). That's 297, not 291.
That said, if I followed your formula, I'd be less than 1% plus presumably 30% errors (326 - .13% - [30% errors]. That seems incorrect?
You would have to get the information from cgminer on the device.
So either SSH onto the box or use the API and a third part App, or use Bertmod and it will show the Hardware errors (HW) on the web page.