Best GPU for mhash per electricity usage?

[Kennji]

I have read that 7970 is the best bang for the buck?

Input please?

[Kennji]

I just noticed that the 7990 is out.  Anyone have any experience with that card?

[Kruncha]

And your right, it is.

But, maybe ASIC is going to make them obsolete...

K.

[Lauda]

GPU mining is becoming less and less efficient due to rising difficulty levels.
But yeah I'm thinking 7970 is good.

[jambaman42]

The only 7990s I've seen cost 900 dollars and probably won't be worth say 3 7950s for about the same cost. Can't really speak as to what is the best. You have to look around. I thought I was getting a good deal on a couple 6950s and ended up going with 3 6870s for the same price and more khash (I'm going for litecoin but the same principle applies)

[Eb0la]

I personally am using 6x 7950's for my mining rig. 

[Lauda]

Note: unless you can afford a lot of gpu's as an investment right now, maybe 7-8 gpu's or more, you probably shouldn't.
Rising difficulty rates :/. Or try litecoin.

[Dossis]

I'm quite much newbie to this mining but from what I've learned is that 7970 is pretty good.

[Lauda]

It's rather simple, a 7970 should give you around 600 MH/s, with the right flags and bit of OC i think you should get 700-750MH/s atleast.
That's decent

[Kennji]

I just figure that I should get a 7970 or 7990 because if asic really does come out I can always sell the 7970 card on eBay or something probably for really close to what I paid for it.  They seem to hold their value pretty well.

[Lauda]

Cheapest 7970: Newegg $399 - 600MH/s average.
Cheapest 7990: Newegg $899 - 1200MH/s average.

Depends how much you can invest. Note: there might not be product available now at those prices.

[MashRinx]

I just figure that I should get a 7970 or 7990 because if asic really does come out I can always sell the 7970 card on eBay or something probably for really close to what I paid for it.  They seem to hold their value pretty well.

Agreed.  I bought quite a fes last summer at $375, a rate I can't even find again today.  They have held their value extremely well so far.  Once the 8000 series comes out, it will be interesting to see, but it's still a very good card.  I would be interested to see how well you can keep a 7990 cool, and if you could really get 2 x 7970 hashing rates.  My understanding is it's basically twice the power at more than double to cost, so just doesn't make sense to me unless you only have a limited number of slots to fill and plenty pf PCI Express connectors available on a nice PSU.

Per the post from LaudaM below, my 7970s are OCd to 1125 (anything beyond that, they get too unstable to be worth it), and I am between 690 - 695.

[VladK]

Obviously 7970 and 7990 are the best ones.
But I personally like very cheap 6930, that could easily get 320, or even 350 Mh/s and cost 80-100$

[ipxtreme]

I think any AMD 5830 is the best bang for the buck. Its hard to find them for sale anywhere.

[kendle]

From what I have been reading the 7950 is very efficient.

[ipxtreme]

true but cost to buy the card is more.

[kendle]

Oh I was comparing 7970 vs 7950.

I currently use 5870's, and they are not easy to find either.

[18RATTT]

I think any AMD 5830 is the best bang for the buck. Its hard to find them for sale anywhere.

whats the Mhash on this card?

[AlphaWolf]

The best card is the one you already own. Spending money on a GPU at this point is a losing proposition for *most*.

EDIT:

Expanding upon that... If you have $400 to spend, spend it on actual BTC.  Then you will have ~4 BTC now.  A $400 GPU will get you 4 BTC... when???  Diminishing returns every 2 weeks, plus electricity cost.  Alternately, you could spend it on an ASIC mining contract, or actual ASIC hardware.  Just not GPUs, if you're expecting to make a profit.

[FinShaggy]

Can you guys help over here?:
https://bitcointalk.org/index.php?topic=180268.0