One of you said it would take one to replace a 7950 and the other said it would take 10 to replace one,
which is it, because it matters.
it only hashes upto 60Kh/s so you need 10 of these to give you 600Kh/s which equals to 1 of 7950
You would need 66 units to equal a 5 card rig
I got my current batch of Vapor-x and MSI twn 7950's for ~ 250 a pop .... so a full 5 card setup was around 1800
they are still pulling ~ 66 watts for for a equiv 7950 ~640-660 hash or ~ 200 watts ...this gives u a 60% power save @ a curennt $98 4 x the price dealio
So realistically they would need to be at least 60-70% cheaper to get to a workable price point considering above numbers
I forgot to add the costs for the 7 x 10 port usb sticks & whatever other extra costs may be incurred due to running 266 of these things for == 4 rig setup
or
1500 for my current 17 rig setup
You are forgetting something with your calculations.
You need to add the BTC dual-coin mining mode capability to come up with a proper cost valuation.
Using the 66 units figure from above, you will also have 115GH/s mining BTC while mining scrypt at 3.96MH/s.
At the new BTC difficulty of 1.789 Billion, that's about .0323 BTC a day SHA-256 mining alone.
Using the past couple of days of poor scrypt mining on the multicoin pools, you would get the same amount of BTC from the scrypt also.
So, lets say based on the past few days of scrypt mining and todays new difficulty rate for SHA-256 mining, around ±.065 BTC a day.