Do I need dummy cards for the other video cards that are not running on xfire? I have this mobo :

GA-990FXA-UD3


https://www.amazon.com/dp/B0055QYKQO/ref=as_li_qf_sp_asin_til?tag=vivithemageco-20&camp=0&creative=0&linkCode=as1&creativeASIN=B0055QYKQO&adid=0DY1SXRBD08MD77X1HN5&

6.  You can't assume that bitcoin difficulty will continue to increase while price will stay the same.  That's NOT going to happen.  We've already seen a level off of the difficulty, and we're still several multiples above the cost of electricity.  Many companies are happy with a 15% margin on their operations - the typical bitcoin miner is operating on 300-400% margins.  Uncertainty of the future will always keep mining profitable for the vast majority, unless/until the price drops significantly from where it is today.  But as long as the price stays the same, or goes higher, mining will remain profitable.

stop babbling dude

a friend of mine sold his 2 month mining 5870 for 40% then he bought: actually he sold for 320$...

I've seen them every time I've opened up a new 5830, 5850, 5870 from various brands.

Yeah good luck with that! I guess you haven't noticed, but the going price on the 5870 is returning to normal. Those cards really are a terrible buy even at that price unless you're short on space.

Here's why.

Today I found a 6970 on Craigslist -- one that's easily available, including NewEgg ($330 after rebate). The Bitcoin mining card comparison wiki lists the card as "easy" to acquire.

The seller was asking $350 for the same card, 1 month used.

What is he thinking? How can you charge a scarcity premium on something that isn't even scarce?

Anyhow, here's the good part -- after I write to him with a lowball offer of $200, he responds with:

"Thanks, Matthew, but I have several people willing to pay $350."

Assuming he's not lying, there are apparently still a lot of stupid people who are about to be very disappointed when they realize it will take ONE HUNDRED AND THIRTY DAYS of mining to pay for that card. That's assuming 8.8c per kWh electricity, and proportional mining (slightly more productive than pay-per-share). That also assumes no further difficulty increases, which is too much to hope for.

Some people have yet to wake up. The time for over-paying for video cards (snatching them up at any price) ended at least a few weeks ago, if not earlier.

For those who have problems with reading comprehension (you know who you are):
No, I'm not saying mining is never profitable.
No, I'm not saying "the sky is falling" or that Bitcoin is going to collapse.
No, I've never said any of the things above.
Yes, I'm saying there are some miners who are going to be *very* disappointed with their expensive toy(s).

Crisis is defined in the eye of the be-holder. Some people can afford to loose time more than others. Loosing 12 hours of mining could mean loosing 1 bitcoin, or loosing 100 depending on who you are.

Tip of the iceberg

Edit: He seems to be a quite violent person who punched out a Marine (he is former USMC), and is almost certainly armed at all times.  Ron Paul supporter, and overall douchebag. 

why are so many people hating on bitcoins?
=[

The 5870 doesn't get even near 440mh/s at stock speeds.

You would have to overclock it *a lot* putting the power consumption to roughly 250-300 watts.

A 5830 doesn't get 310-320 at stock either. That's the absolute maximum with the voltage and core frequency sky high (past 1ghz).

You guys are wasting your money.

Sigh, all the pools are having issues right now

Difficulty affects price and vice versa, but there are other factors to consider as well.

Usually when I see something be referred to as a Chicken or the egg problem it's simply a misunderstanding of logic or the nature of the specific underlying problem. This is no exception, what you're talking about is a feedback loop, there is nothing weird about it and is omnipresent in everyday systems, including our body. The "Chicken or the egg problem" itself arises from inconsistent definitions, it's the same as asking whether a fixed object would move when pushed by an irresistible force.

^^ this.

Right now next dif extimate is at about another 10% increase, or ~1.727mil 
This does not account for the large amount of hardware still being bought that is not online yet and the lag behind price which has recouped some today.

who said it was going down?

I don't house sit and I'm not much of a pretender.. Sorry.