The Most Efficient Rig

[Fakeman]

Pulled those from one of the other charts, changed it so it's just MH/s/$.

[oyster2000]

6950 might be a good option, but remeber you need 2 x 6+2pin 75w adapters from your PSU for each 6950 (only needing the 6pin)..

do you think it would be possible to get 4 x 6950 up and running with a 1200 PSU ... you would need 8 x 6+2pin connectors...

http://cgi.ebay.co.uk/4-8pin-Power-Lead-Cable-Cord-ATI-Radeon-HD-5970-/400217316751?pt=UK_Computing_CablesConnectors_RL&hash=item5d2ecf9d8f

Think adding a couple of these from the molex would do the trick?  Most 1200w PSU only have 4 x 6+2pin connectors

[steamboat]

a 1200 watt could run 4 6950's, but youd be operating at close to 100% depending on the rest of your setup. i'd recommend a 1500w, and AFIAK there's only one.

[Jack of Diamonds]

stats

That table is wrong because it lists the entire power consumption of the system.

Come on, think. A 6950 has 2x 75w power connectors. And it draws a max of 75W from the pci-e slot.
That comes to a total of 225 watts. There is no way it can *physically* go above that.

a 1200 watt could run 4 6950's, but youd be operating at close to 100% depending on the rest of your setup

4x 225W = 900W

[hugolp]

your numbers are way off for the 6950 2gb.

i'm running 2 @ 400mh/s pulling 220watts per card.

The numbers are way off on a lot of them. I doubt that the 5870 consumes 270W.

[SchizophrenicX]

I think the numbers are wrong, I've been reading on a number of people running 4x5850 on 650 W~700 W. I believe there is a cause for update in the hardware comparison chart.

Anyway, back to topic. I think if you're looking for something that fits your description you'll have to go
1. go to a cybercafe
2. bring thumbdrive w/ wallet
3. log in to your favorite exchange
4. do some trading
5. earn some money

Most power/cost efficient while still can be traded away (quite) easily in the future

[Basiley]

doing BTC transactions/traffic in uncontrolled envrionment[such as "cyberfee", public/social/govt network/nodes/teminals and etc and etc] can lead to inpredictible/unwelcomed/unintresting consequencies.
just imagines - simple USB-traffic-sniffer, code, combined with custom rootkit/bootkit and viola !!
and thats pretty usual setup in some corporate network, let alone, compromised hosts of cybercaffee.

[MCWey8]

4 x 5770 - 932 MH/s - $400.00 - 400w = WIN

and the mining hardware comparison shows the 5770 at about 100w .. not 213w

[Jack of Diamonds]

4 x 5770 - 932 MH/s - $400.00 - 400w = WIN

and the mining hardware comparison shows the 5770 at about 100w .. not 213w

Those are semi-hard to find though (new and boxed), and you need the rest of the system around the cards.