Topic: High efficiency GPU mining - 3 MHash/J (Read 7231 times)

Assuming I can find 4 or 8 to buy in a job lot...

...how much do these 5970 cards cost?

I've got a bunch of rigs that currently eat around 3 kW but space-consumption and heat output is starting to piss off the girlfriend. The benefits of being able to dry all the laundry at high speed by hanging it up in the 'mining bedroom' is being outweighed by the lack of space in the 'mining bedroom' to hang anything up.

So I'm looking at increasing the density of my rigs - swapping my collections of 5830s, 5850s and some 5770s (single slots... good for what they do) for half or a quarter the number of cards would be a Win. Especially if I could get 3 megahash/sec from one frame rig. Hell, I'm only getting 4.8 gigahash/sec from four rigs and 17 random GPUs.

Using 8 cards that have dual-GPUs would give more (better GPUs as well as nearly the same number of cores) - and would either be nice and spacious in two frame rigs, or with a bit of ingenuity, would pack into my mk3 rig (with serious attention to cooling).


However, I have the suspicion that one of these cards costs as much as the total cost of one of my rigs. Yeah, I could reuse logic boards, extenders, all that jazz... but I'd need HUGE new PSUs (expensive) along with the mega money cards.

Anyone here got an 'in-the-know' trade price for a 5970 in the UK? I know how much the online shops quote, and they're all out of stock so the prices are irrelevant. I wouldn't buy a GPU from eBay - too many stories of 'enthusiasts' going too far with overvolting and overclocking, permanently making the card unstable, then selling on eBay as a functional GPU. They take so damn long to diagnose as a real hardware failure (rather than a software config / BIOS / EFI problem) that I'm only interested in new parts, or unused parts.


I have the feeling I'm asking for the impossible. Am I? Should I stick to 5850s as and when I find reasonably priced ones?

Thanks for all helpful input!

I may be wrong but I don't think most people subtract out the idle rig consumption when calculating their MHash/J value.

I don't see why that would make sense unless you're calculating the difference between your normally-on system and what it uses when mining. But that doesn't transfer well to comparing with other users doing mining.

Phelix, if I may humbly suggest that you try at least CGminer. It will reduce your command prompt windows to 1 and do the same thing that you're doing with equal Hashpower.

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You saying reducing or under volting gives same Mhash with less power used?

your clocktweak can't really change the voltage of my cards though.
i dropped some of them to a lower voltage, still pulled the same wattage from the wall.