3. I restart wallet in my i7 windows machine, hashrate dropped from 160k to 5k, whereas my other windows machine remain same hashrate as previous (I did not restart the wallet). And yet, after restarting my i7 wallet, it is very laggy, some new calculation required more cpu power?
I think this may be true, because I have the same problem with my i7-2600k. It has a very low hashrate compared to the other machines proportionally as of before f7000. Maybe i7 is not efficient for the new algo?