I don't quite understand why people are still buying mining hardware. Currently it will take about a minimum of 4 months to pay off one card.
I picked up 5 5850's for 145 each and you cant tell me that is not a bargain. I have tested each and the average between them is about 390 megahash. That's .208 a day for this difficulty. I recognize that the difficulty will increase but I'm going to stick with this for simplicity sake.
Now I'm not a dumb ass and I am not selling at the listed price of around 11 dollars. I agree selling at 11 dollars would take a long time to get your roi. I plan to hoard until the price goes up to between 15-20 dollars. So in 30 days I'll have 6.24 bitcoins which is $93 dollars at 15 a btc or $124 @ 20 a btc.
If you take the cost of electricity the card costs $7.2 a month (I pay 6.7c a kwh) That means $86 or 117
Also a months time is only two difficulty increases so my profits wont get drastically lower. Since in a months time the cards will be more then half paid for it still is 100% worth it.
testing them and running them for days on end overclocked to the nuts are two very different things.
i would be hesitant to tell someone to expect more then 375 mh/s from a 5850 on average. A minor difference
from your 390 but it all adds up when discussing 5 of them. For every time a card hangs and it takes you time
to realize it and fix it.. has to be factored into your mining results.
just my opinion. i realize some 5850s perform better then others but a 990-1000 core clock speed, stable for days and day,
is impressive on these 5850 cards.