Dual gpu

[bruteoger]

I was wondering whether or not I can use a 5770 and a 5830 on guiminer on the same computer.  I can get both to set up separately but together I can only use the one with the primary adapter in ccc.  The other gpu is considered a disabled adapter. 
Iam on windows 7, iam currently running the 5830 on deepbit at 285 or so.

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[Bert]

Under Windows you will either need to plug a monitor into each card, use a crossfire cable or there is a hardware trick using a DVI to VGA converter and 3 x 68/75 Ohm resistors which fools windows into thinking that a monitor is connected.

[bruteoger]

Tried the dual monitor, got both the screens up but Guiminer only counts the 5830 cypress.  Crossfire I was told is impossible as 5700s and 5800s don't crossfire and the trick sounds about the same as the dual monitor, any other suggestions?

[Bert]

With the second screen attached, did you try reinstalling the drivers, windows is weird like that at times.

[Bert]

Come to think of it, On my Windows machine I couldn't see both my 5870's using phoenix until I enabled crossfire.

With Ubuntu on my second machine I had no issues at all, maybe install Linux ? http://forum.bitcoin.org/index.php?topic=9239.0

Both cards do support OpenCL.

So any issue in accessing both of them is the windows drivers.

Here is something that I didn't try, installing ATI's OpenCL drivers separate from the version that came with the GPU driver package that I downloaded, maybe that might work for you. http://developer.amd.com/sdks/AMDAPPSDK/downloads/Pages/default.aspx AMD-APP-SDK-v2.4-Windows-64 or AMD-APP-SDK-v2.4-Windows-32

[bruteoger]

Thanks for the suggestion but eh, sister wanted her monitor back, I'll try it later.  Does anyone have any suggestions for a solo screen comp on how to get these 2 gpus running?  Hmm, I'll try linux I suppose, would rather not have to go through the process of doing all that installing again, so I'll wait until tomorrow if someone puts up a different option. 
Still thanks bert for all the info.

[Bert]

Sorry I couldn't help, hopefully someone who knows more about windows than me can.

[tokn]

Thanks for the suggestion but eh, sister wanted her monitor back, I'll try it later.  Does anyone have any suggestions for a solo screen comp on how to get these 2 gpus running?  Hmm, I'll try linux I suppose, would rather not have to go through the process of doing all that installing again, so I'll wait until tomorrow if someone puts up a different option. 
Still thanks bert for all the info.

Have you tried the dummy plug as previously suggested?  Takes all of 2 minutes to rig one up, if you live in the US and have a radio shack nearby they sell the resistors for .99 for a pack of 5.

http://forums.bit-tech.net/showthread.php?t=167450

[sofadigger]

here is a simpler solution

http://blog.zorinaq.com/?e=11

http://blog.zorinaq.com/images/simple-dummy.jpg

i couldn't find a 75ohm resistor so i tried a 100ohm one and it worked fine.
i had to refresh the displays in ccc.

[bruteoger]

Alright cool, Ill go buy a risitor later.  Cool thing though, my sister left and I re installed all the drivers, now their both up and running(Thanks bert!).  Thanks for all the help guys.