Bitcoin Forum

Hello everyone!

Can you please advice me if it is better to go 2x7870xt or 1x7970? I am leaning towards 7870xt choice. Also if 2x7870xt, can you recommend any psu? Ot at least power required, 660, 800W?

Thanks in advance!

What are you planning to mine SHA-256 or Scrypt?

It make a little bit of difference on what models of cards to buy. The usual debate is between 7950 VS 7970. I would go with a 7950 (cheaper and less wattage).  You will want too minimise your power consumption and go with as few as GPU's as possible. For power supplies you need to look at the amount is 12V amps delivered not total wattage. GPU's eat amps like crazy. A good 850 supply Corsair Bronze will drive 2-3 7950's or 2 7970.

MrBSmith

LTC LUwVTpW14FvbfVFz7YNNhjsA3FUZUXQgDu
BTC 1KkGkBPsMMyV8ccgsywgQmVgmpZL5fEQzc

Thank you for your answer :)

Seems that i will go with 7970 then and buy any bronze psu. Damn i wanted those 7870 to get to 1Gh/s :D

You can get 7970s. I think they use 200 watts/each so you need to multiply 200(number of GPU's) + like 150 watts to spare. Try to go for the most efficient PSU's to save electricty.

Unfortunately my budget is limited. Its either 2x7870xt or 1x7970.

Now I am browsing for 7970 with unlocked voltages, any suggestions? Seems Gigabyte is locked.

I'm leaning towards 2 x 7950's or 1 x 7990's. They both do around 1GH/s.

Mine pulls about 210W from the wall @ 1100MHz core, 950MHz memory and 260W from the wall @ 969MHz core, 1700MHz memory (scrypt).

Just FYI.


It seems like some of the Gigabyte cards can hit higher hash rates than the rest. I have a Sapphire hashing at 660Mh/s (660kh/s for LTC). Whatever you do, get one with a nice cooler. You don't want it running at 85C all day long.

This

Thank you for all the answers

I am buying 7970 sapphire or XFX. Gonna mine sha, but planning scrypt aswell when btc rises with difficulty too much.

This might help too (comparison of power consumptions):

http://us.hardware.info/comparisontable/442472/geen_username/graphics-cards-comparison-table-05142013-0455-pm

Link does not work

Managed to get my own list, thanks for the link :)

Good choice on the 7970!

My 7970 works really well, but it runs very hot, I have a fan aimed at the open pc case next to an open window, it'll be brutal this week when it's getting hot outside.
I was thinking about going water cooling with it, but that's another $200 on top of the cost for only a few more months of profitability.

I suggest you 7970

i have two  7950  and ill add a third one soon , they are the best price/hash power out there

If you are planning to mine SHA-256 it might be good to wait around and buy a Butterfly Labs ASIC 5gh/sec miner or if you are impatient you can buy one on ebay right now for around $500.

As long as I know, 1 7870 makes about 350 MHs ... I think you need 3x7870 for performing over 1 GH/s.
It is better 7970 or 7950.

I really wouldn't waste my money on GPU mining anymore, check out the difficulty graph here http://bitcoindifficulty.com/

There are so many asic machines coming on-line that the difficulty is going to skyrocket even faster and you'll be lucky to make a few cents a day even before all your costs.

Ye ye, I have been hearing about end of GPU mining for weeks. Even if it comes which I doubt, I will just sell my 7970, no harm done. (But still remember about ltc, you cant asic mine these).

I would def got with the 7870xt

I'd say definitely get on Newegg's mailing list.  They have alot of 48-72 hour promotions.  I got my Powercolor 7950 for $270 and free shipping.  That is...if you have any patience.  :)

Yes newegg is a good point for starting and  feedbacks of owners are useful.

7920x is much faster and better.