6x RADEON 280x/290/290x/ MINING RIG ADVICE

[litec0in]

MSI Z87-G45 Motherboard or GIGABYTE GA-990FXA, 8GB 1600Mhz ram, 8GB USB Linux(BAMT?). 2x Milk crates.

290s 250W/12V=21Amps x6=126Amps
6x 290 @ 250W=1500W
2x 850W PSUs?
Powered risers on cards 4-6
From what I've read here, the 280x and the 290 consume the same amount of power 250-270Watts.
Any gain in PSU efficiency using a 220V outlet?

290   840Kh/$500=1.68Kh/$
280x 750Kh/$400=1.87Kh/$

https://litecoin.info/Mining_hardware_comparison

I've been running a single 290(stock 1 fan) 24/7 for a month now, getting 840Kh(1000/1500 OC) 79˚C 4500rpm in the garage(32˚F).
The better hashrate for slightly more $, seems to favor the 290s, but I can see how 2 fans are better than 1.
So should I get the 280x just because of cooling, having 2 fans instead of 1?

Anyone a reseller with Ingram Micro, Techdata, D&H? Are there prices any better than Pricewatch? Any other sources?

[1715365679]

1715365679

[1715365679]

1715365679

[Silvano]

250w for R9 290??

here they said a little bit more......
http://www.techspot.com/review/736-amd-radeon-r9-290/page8.html
here too..
http://anandtech.com/show/7481/the-amd-radeon-r9-290-review/15

i don't believe u can mine over 800 Khash/s undervolting cards at 250w (­±1.045V)

[litec0in]

Those charts watts include the cpu/ram/motherboard etc(system). Anandtech says system 383w full load. I'm guessing the 290 card by itself is 250-270watts.

[kikeda]

Those charts watts include the cpu/ram/motherboard etc(system). Anandtech says system 383w full load. I'm guessing the 290 card by itself is 250-270watts.

Goodluck with that, for $200-300 more you can get a decent 1200w psu that can power your system + 3 290 and another 1200w psu for the other 3 290 i'd rather be on the safe side considering the 290 cards cost around $500+ each.

[Wipeout2097]

Since the 290's cannot be undervolted afaik, you need at least a 850W for the base system and 2 cards, then a 1300W for the remaining 4.

I suggest a Corsair TX or a XFX Pro 850W and an EVGA Supernova 1300W.

[akaCash]

I'm getting 860 Kh/s from my 2 270x's, and I paid less than $200 each. $194 x 2 = $388 for about 860 Kh/s. Not sure if it's feasible for you to run twice the cards, but it's a much better value. It's the main reason I got these instead of the 280x's. Plus they're a lot easier to find, but do with that what you will. Just wanted to throw it out there.