But, your investment needs to be proportional to your return expectations.
Power is definitely a consideration, and is usually a big chunk of your balance sheet.
Throw some numbers into a calc and see where you're at before you spend money.
Assume difficulty will average around 15% every 10 days.
And see how close you get to your goal.
Assuming that you have a spare PSU lying around, and you have an electricity price of $0.07/kwh, you wouldn't profit, not even being optimistic and assuming 20% difficulty increase/month.
So no, give up already, unless you can get millions in hardware in bulk, and then get access to really cheap electricity.
It's hard to tell on difficulty we got one that was not bad last week. I'm hoping to see more like that but i think will be slightly over 10 this week, but i could be wrong. Time will tell.
Sep 13 2014 29,829,733,124 8.75% 213,529,547 GH/s
Aug 31 2014 27,428,630,902 15.03% 196,341,788 GH/s
Aug 19 2014 23,844,670,039 20.86% 170,686,797 GH/s
Aug 08 2014 19,729,645,941 5.30% 141,230,307 GH/s
Jul 25 2014 18,736,441,558 8.08% 134,120,673 GH/s