Bitcoin Forum

I am researching but thought would ask too,  I am building my first gig and looking at buying Ati cards.

What model Ati card is recommended? can you advise the mining rate of some models or how can i find out ?

What motherboard should I get that would support adding few of these cards ? What slots need the board to support to hold multiple Ati cards, was it pci-e or something ?

Any hearing issues with having say 3 cards on one motherboard ?

The CPU doesn't matter I guess.

Buy 6990 if you can (within reasonable price).

gygabyte 7950 3 fans ;D

look at this : https://bitcointalk.org/index.php?topic=163306.0

The 6990 is very hard to find. There is one a Amazon right now for $700. I was making the same search you are last week. The most recommended new card, I have seen in this forum is the 7950. I ended up buying a 7970. On stock setting I am getting 604MH/s.

keep in mind the newer rev2.0 versions are voltage locked.

they are mining BEASTS. I can, in a decently cool well ventilated environment get 670 khash EACH from them.

they also get 630 mhash at 1200 core clock.

the rev1.0 can't get quite as high as its VRM's aren't heatsinked and will overheat at over 1150mhz, they are voltage unlocked though so they are much better if you want to run at something less than maximum clock speed.

source: i have some of both :)

I recommend the 7950's.

How hot is your 7990 running and what fan speed? If you haven't lowered your mem clock, it would help lower temperatures (or some people say) although I haven't seen significant improvement with a 6970.

+1 curious to see how hot the 7990 runs.

shouldn't a 7990 see at least 2x600Mh?

I recommend 7850's. Only cost $100 each (I craigslist/ebay the games).

Im going to leave my math here, and head in shame. I just fucked myself out of free money.

2 7850's = $200 = 640 (+/- 20) M/hash
1 7950 = $250 = 540 (+/- 20) M/hash

That is $250 you save per rig. Which ends up covering the cost of another rig to make up M/hash

My 2, TWO, rigs = $1500 with 8 7850's = 2300 M/hash

When I get my riser cables I can add 1 more gpu per board. Which = $1700 at 3,000 M/hash

4 x 7950 = 2200 M/hash = $1350 on same hardware. Or 5 x 7950 = 2750 M/hash at $1600

Please note im calculating the games combo being sold for $50, into the price of both GPU'S.

Its 5 O'clock somewhere.....Errr 5 AM here. Im going to be pissed in the morning when I double check these figures to find out I cheated myself.

ALSO THE 7950'S ONLY REQUIRE 30 MORE WATTS AT DOUBLE THE M/HASH FFS.

I would recommend the gigabyte 7970s. 3 fans = cool. O.K. they are voltage locked, but no issue with running them on max.

Correction I said 7990 and meant to type 7970. Temp is 63c fan is at 73%. At stock settings. I get 604MH/s running stock. Increasing the cpu clock setting to 1100mhz gets 657MH/s but temps increase to 70c. GPU is in a Coolermaster Hafx. I would prefer to keep the card below 70c. I Not sure of the max temp for the gpu.

You are correct I made a typo, card is a Gigabyte 7970. Clicking the overdrive get 657MH/s
temp is 72c atm.

Gpu mining for bitcoin? You might as well be throwing money in a burning fireplace.

And what else you recommend using? Maybe the world famous BFL ASICs? lol

also avalon asic, are too slow in shipping, they take 6 month+

when you guys think that asic become more of a staple, for mining?2014?2015?

I'm using triple fan gigabyte 7950. I get 612 kH/s (24 h average LTC, should be about 612 MH/s BTC) at 1150/1400. powertune +20%.
62°C with fans at 100% (about 3600 rpm) ambient temp. about 23°C, very loud.
with temp. target at 75 °C the fan is working with about 2100 rpm. at/above 80°C it is getting unstable. no hw errors.