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Bitcoin => Mining => Topic started by: jasonk on June 02, 2011, 08:48:29 AM



Title: 2x 5850's and 1x 5830 in the same machine?
Post by: jasonk on June 02, 2011, 08:48:29 AM
I have 2x 5850's in an existing miner machine.

I have a spare 5830, and I'd like to use it, but need a ribbon cable to PCI-E 1x.

My main question is, how do you manage overclocking different cards?

MSI afterburner only has 1 slider.  Any tips or tricks?

Thanks!


Title: Re: 2x 5850's and 1x 5830 in the same machine?
Post by: Shades on June 02, 2011, 10:13:31 AM
There's no problem connecting one additional card (as long as your PSU supports it). Just use a dummy plug - http://www.overclock.net/folding-home-guides-tutorials/384733-30-second-dummy-plug.html (http://www.overclock.net/folding-home-guides-tutorials/384733-30-second-dummy-plug.html) to make the driver think there is a monitor attached to the additional card.

Overclocking with MSI Afterburner works good. You just need to "unlock" the software to make all overclocking options available. An example how it's done - http://forums.guru3d.com/showthread.php?t=327291 (http://forums.guru3d.com/showthread.php?t=327291) This should enable you to tweak all your cards. You can switch between them via "Settings>General tab".


Title: Re: 2x 5850's and 1x 5830 in the same machine?
Post by: Meatball on June 02, 2011, 10:40:39 AM
In the MSI Settings section (General Tab) there's a drop down for the GPU.  Just pick the one you want to work with and any changes you make will only affect that card.  I'd uncheck the "Synchronize settings..." button as well and just do each card manually.  I have one machine running a 5850 and 2 5830's using that setup and I'm able to update each card individually.


Title: Re: 2x 5850's and 1x 5830 in the same machine?
Post by: Reckman on June 02, 2011, 01:48:15 PM
 Or just use AMD gpu clocking tool (not CCC)


Title: Re: 2x 5850's and 1x 5830 in the same machine?
Post by: jasonk on June 02, 2011, 08:27:18 PM
Thanks guys, quite helpful.

My PSU is a thermaltake 775W w/ 64A 12v rail.  Current load on it is only 370W.  Assuming 85% efficiency, its only using 315W (2x 5850's + sempron 140).

So I know it can take the extra load easily.

I don't know if i'll bother with the dummy plug... The system has not been rebooted in about 10 days.


Title: Re: 2x 5850's and 1x 5830 in the same machine?
Post by: Meatball on June 03, 2011, 01:26:29 AM
If you do have a problem, dummy plugs are insanely easy to make.  If you have any of the DVI to VGA adapters laying around that came with the cards you just need 3 resistors that you can pick up at Radio Shack in a pack of 5 for a buck or two.  Search on dummy plugs and there's a good post with screenshots out there.