Mhash and expected BTC 40% difference

[ddd1]

I have ~1380Mhash, according my calculation 24/7 that should be 28bitcoins/month,

However Ive now mined couple of days and multipied with 30 I only get it to 20Bitcoins a month?

it's 2x 7950 420Mhashx2= 840Mhash and 1x 7970 500-540Mhash so in total it is 1340-1380Mhash.

[DeathAndTaxes]

"However Ive now mined couple of days ..."

Its called variance.

Also fees, downtime, fluctuations in hashrate, and stale shares reduce your income.  You are paid on valid shares delivered.

[crosby]

Where are you mining ?

[shakaru]

Possible reasons...

1) your share output is not as effencient as the reported hashrate.
2) your loosing connection 30% of your mining time and getting rejected shares.
3) Your mining payments are based on the blocks found by the pool you are on and divided by shares submitted. The pool your on might not be as good as it looks. Also, some days are better than others and you just need to wait.

[ddd1]

thanks for the help, I'm sorry I gave insufficient info in original post.

I'm mining on Deepbit and chose proportional so the fee should be 3%.
I have checked and no disconnection in internet.

My impression is I should be getting my mhash regardless of how lucky my miners are?

Edit--> I forgot my stale is 0.08% according deepbit.

I'm mining with Guiminer opencl.

[DeathAndTaxes]

My impression is I should be getting my mhash regardless of how lucky my miners are?

Your impression is incorrect.  There is variance in finding blocks.  If the pool should have found 120 blocks in the 3 days you were mining but instead found 102 then you would receive 18/120 = 15% less revenue.

Also prop pools can be pool hopped.  Pool hoppers steal your money (you earn less than expected value) and they earn more.  Mine in hop proof pools (PPLNS, PPS, SMPPS, etc).  Hoppers can reduce revenue of suckers like you by 20% or more.

You likely don't have 0 downtime.   You can check.  At 1.38 GH/s you should produce 1157 shares per hour.  Check how long you have been mining to number of shares submitted.

Fees and stale reduce payment so even under optimal situations and without any variance you would never make 28 BTC.  At best with 3.08% lost to fees and stales you would make 27.1 BTC.

[siggy]

This may not be your whole issue, but DeepBit prop has had absolutly horrid luck the past 24 hours... by my calculations, they are down around 14-15%...

Sigg

[ddd1]

My impression is I should be getting my mhash regardless of how lucky my miners are?

Your impression is incorrect.  There is variance in finding blocks.  If the pool should have found 120 blocks in the 3 days you were mining but instead found 102 then you would receive 18/120 = 15% less revenue.

Also prop pools can be pool hopped.  Pool hoppers steal your money (you earn less than expected value) and they earn more.  Mine in hop proof pools (PPLNS, PPS, SMPPS, etc).  Hoppers can reduce revenue of suckers like you by 20% or more.

You likely don't have 0 downtime.   You can check.  At 1.38 GH/s you should produce 1157 shares per hour.  Check how long you have been mining to number of shares submitted.

Fees and stale reduce payment so even under optimal situations and without any variance you would never make 28 BTC.  At best with 3.08% lost to fees and stales you would make 27.1 BTC.

Thanks, I'm still beginner when it comes to this stuff.

Now checking my deepbit it has increase to 0.72bitcoins/24h, ignoring variance with the difficulty and 1.38GH/s it should be around 0.93bitcoins/24h?

For deepbit past 24h the average solving is 0h 31m, how do I calculate if that puts me at 0.72bitcoins or if I should be getting more/less?

As for downtime I'm not sure, I have wery good internet it's 99.999% online

[check_status]

How long have you been mining and how many shares have you submitted? (as per DAT)