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with the following caveats;

- currently available in qty 20+ from single source of the exact same model (or 10+ if dual gpu card)
- be new or refurb with at least a 30 day warranty
- is based on my experience with reference 5850's pulling a steady 375 Mh/s

i'm ready to expand and can't really find anything that beats them (not saying there isn't i just can't seem to find anything) - plus i've had great experience with the 2 of them i've tested thus far so i'm a bit biased.....

thanks

Perhaps you should wait for 7990s. It will cost quite a bit, but you will get power efficiency, space efficiency, latest architecture, and will be pulling 1.2-1.5 Gh/s according to my calculations.

According to your post, 5850s $149 for 375 Mh/s comes out to 0.397 $/Mh/s.
If the 7990s cost $800 and pull 1.2 Gh/s, it comes out to 0.67 $/Mh/s.

However, you will need 4 5850s to do the job of 1 7970. The wattage to run 4 5850s is 400*4=1600W (taken from http://www.xbitlabs.com/articles/graphics/display/radeon-hd5850_11.html#sect0). The wattage to run 1 7990 is guessed around 400W (https://bitcointalk.org/index.php?topic=63447.0), saving you 1200W.

So, with 5850 you will need more space, ventilation, PSUs, motherboards, and money spent on electricity bill. Of course, there is also resell value.

Unless my Kill-A-Watt is broken that figure is crazy my 5850 takes 230w, full GPU usage during hashing, from the wall according too it. That is whole machine single slot board with pentium 2180 1gb ram and hard drive with all unnecessary devices turned off in BIOS clocks set to 900,300.

thanks, i've considered waiting for the next gen cards to either buy directly or see what they do to the market ($) for existing high end cards.  but without firm release dates as of yet i'm wasting opportunuty by staying on the sidelines.  i may go with a hybrid approach since i have a few different PC platforms to work with - load up on some 'oldies but goodies' and keep some cash in reserve for the new stuff.

i'm not sure how they came to those power #'s but my 2 reference 5850's loaded in a barebones (1 stick ram, no hd, ....) old P4 system pull 363W.

The deal at BensOutlet.com for new 5870s for $139.99 was pretty good. *shrug* Too bad they're all gone now.

I bought a 5750 for 50 euros shipping included some time ago. At 170+ Mhs may beat your 5850's Mhs/$.

I was under the impression that if one included the cost of power and other components, rigs like the BFL singles were your best bet?
I am likely very wrong so someone correct me otherwise.

yes, i'm sure that if those are factored in something else may easily be a better option.  but for me, until i run out of free/ultracheap PC's, space, or free power they are not a concern. 

not necessarily directly related to what my advertised goal is but if all things are equal on the Mh/$ front i would rather go with gpu's.  i'll wager that should the bitcoin system crash for any reason, or i decide to get out, that i can better recoup my investment by reselling gpu's than custom FPGA/ASIC devices.

You are correct. They pull ~200W way less than 400W.  ;)

well, i actually did find something that will beat it and jumped on them - 5830's for $108.  for my initial 10 rigs i'm now in for $55 over my $2500 investment 'funny money' allocation but did stick to all other goals.  end result will soon be 4x5850 and 16x5830 running in 10 HP P4 desktops on BAMT.  my somewhat educated guess is that i should get me north of a steady 6 Gh/s.

i'm prepping a few other platforms for 4-6 high end gpu's per system but will wait a bit to decide what direction to go with those - plus i'll be busy for a few weeks getting the other 8 of the above systems up, running, optimized, and stabilized.

Personaly, I think the 5850s are about the best ones on the market, at least for my unique setup. 

On ebay you can find them for about 150 for the Sapphire xtreme 5850 and at 850/300 im getting 350 Mhash.

Its a nice low-ish price, fairly good with power draw.


With the new cards comming out and testing I have not seen any big improvements.  If im going to drop $600+ for a card, I want it to have a 10% or better improvement on Mhash verses 4 of the 5850s.  (ie  Four 5850s=1400 Mhash, one New Card = 1500 or better)

While the power thing is important, if the power draw is a big thing for you, you always have the option to go FGPA.

Just my 2 cents

-elrodvoss

I have a system with dual 7970's and it pulls about 600+/-watts at the outlet. That includes AMD Phenom II x6 CPU, dual SSDs, and RAID1 2TB mass storage. Using GUIMiner v2012-02-19 I get about 1Gh/s combined, each individual card does about 500Mh/s. However I do not think AMD has the drivers tuned yet for these cards, nor do I think I have GUIMiner exactly optimized for this system.

Just my 2oz of copper.

Thanks,
The 1911Moocher

I'm running dual 7970s as well (see this post (https://bitcointalk.org/index.php?topic=74220.msg828518) for details).

I get 625 Mh/s from each card stable at 80-85 degrees C with these cgminer options (latest AMD drivers and SDK):


These XFX-made 7970s don't have the best airflow, in my opinion. I should have bought dual-fan ones... Then I would have been able to get 700+ Mh/s out of them!

Vindimy you are right, I have the XFX 7970's and they do not get good air flow. My one 7970 runs at about 93 degrees all the time while mining, but I am running three monitors off of it at once.

I took your CGminer flags and modified them for GUIminer and still can not get much better then 620Mh/s on one card and 490Mh/s on the second card. Vindimy do you have your cards connected with a CrossFire cable?

Well I figured out my problem I was using -f 0 which was limiting the cards. Took it out and now I am running BttW and getting a steady 620 Mh/s and 610 Mh/s out of both cards. Probably need to go fix my other machines and take out the -f flag.....such a newbie mistake on my part.

hi , i think 5850 are the best in Mhash to usd ratio , and watts are about 180w , i have them 4 in one comp on gigabyte ud7 and stable running on corsair 950w psu with sempron 140 and 1 gig ram on board, so buying bigger psu is wasting of money,

If I may ask, what are you getting for hash rate on each card?

i can get over 375 MH/s without overvolting