Can a hd6950 and hd6770 share the same machine?

[mmartoccia]

I'm trying to run both cards on the same machine. Both cards run under XP independently but when both are in the system, it only sees the 6950. Is it possible to get these two to play together nicely where they both show up?

[1715070949]

1715070949

[freynder]

I'm trying to run both cards on the same machine. Both cards run under XP independently but when both are in the system, it only sees the 6950. Is it possible to get these two to play together nicely where they both show up?

I'm running different models (6870 and 5870) on the same MB in Ubuntu without any issues. Not sure about Windows.

[mmartoccia]

Is there a trick in terms of the order they need to be installed, driver installed, etc... It seems to me that the drivers are conflicting with the 6950 being dominate. Anyone else have success with two different models of ATI working together with catalyst 11.7?  I am running Windows XP.

[deepDown]

I'm trying to run both cards on the same machine. Both cards run under XP independently but when both are in the system, it only sees the 6950. Is it possible to get these two to play together nicely where they both show up?

They definitely should work together.
I believe that the problem is that windows will put the secondary card to sleep if it is not:
a) crossfired with the primary card
b) connected to a monitor
c) tricked to believe that it is connected to a monitor with a dummy plug

Take a look at:
http://forum.bitcoin.org/index.php?topic=27929.0

Also you can try using Linux for mining there  you wouldn't need dummy plugs -  I strongly recommend it
There is even a linux built specifically for mining
LinuxCoin - http://forum.bitcoin.org/index.php?topic=29021.0

cheers

[mmartoccia]

b) connected to a monitor
c) tricked to believe that it is connected to a monitor with a dummy plug

I'll have to give that a try.  Its currently a headless system so that could very well be the problem.

Thanks for the idea's deepDown!

[deepDown]

you are welcome!

Just to make it clear, as you quoting only b) and c) makes me think I wasnt, it is a) or b) or c).
So if they are already crossfired they should be recognized and active in Windows.

Though, if it is the case that they can not be crossfired together because of different architecture - than you can try b) and c)
E.g. my 6950 and 5870 do not like each other   so crossfire-ing is not an option.

[mmartoccia]

Tried the dummy DVI and no go.

I think this is more motherboard than OS.  I'm working with an older Socket 939 EVGA 133-k8-nf41-ax.  It has 3 PCI-e lanes, the two on the end are x8 with the one in the middle x16. 

Think this could be the issue?

[jh1523]

Don't think this is the problem.

You mentioned it's a headless system. Do you have dummy plugs on both cards? In windows each card that's not connected to a monitor needs one. Can you confirm they work if each is connected to a monitor? If so, that's the problem right there.

[mmartoccia]

It was headless, I've since connected a monitor to the 6950 and a dummy DVI to 6770.  I've swapped configurations and regardless of position in the PCIe slots the 6950 is the only one visible by the BIOS or Windows.  If I connect the monitor to the 6770, the dummy on the 6950 the BIOS does not see it and the monitor fails to activate.  Still, when only one card is used, it works.  I am at a complete loss.   

[jh1523]

Sorry, I'm also at a loss. I even tried googling, the only hit is for the same question you asked yesterday on overclockers forums (fellow overclocker here).

Again, I don't know. Try an older revision of the drivers. Or try tweaked drivers such as http://www.tweakforce.com/modules.php?name=Downloads&d_op=viewdownload&cid=20

[acebmxer]

Have you tried to

1. Uninstall all ATI drivers.
2. Download and install Driver Sweeper. (If you dont have it already)
3. reboot into safe mode.
4. Run Driver sweeper and remove all ATI drivers again.
5. Reboot into windows.
6. Install ATI drivers.
7. Reboot when installer tells you to.

See if that works.  Thats what I had to do when I added my 5830 to my 5850.

[mmartoccia]

Have you tried to

1. Uninstall all ATI drivers.
2. Download and install Driver Sweeper. (If you dont have it already)
3. reboot into safe mode.
4. Run Driver sweeper and remove all ATI drivers again.
5. Reboot into windows.
6. Install ATI drivers.
7. Reboot when installer tells you to.

Should I do this with both cards installed or one at a time?

[acebmxer]

Have you tried to

1. Uninstall all ATI drivers.
2. Download and install Driver Sweeper. (If you dont have it already)
3. reboot into safe mode.
4. Run Driver sweeper and remove all ATI drivers again.
5. Reboot into windows.
6. Install ATI drivers.
7. Reboot when installer tells you to.

Should I do this with both cards installed or one at a time?

Yes you can do this with both cards installed.

[MrWizard]

Have you tried to

1. Uninstall all ATI drivers.
2. Download and install Driver Sweeper. (If you dont have it already)
3. reboot into safe mode.
4. Run Driver sweeper and remove all ATI drivers again.
5. Reboot into windows.
6. Install ATI drivers.
7. Reboot when installer tells you to.

Should I do this with both cards installed or one at a time?

Yes you can do this with both cards installed.

Don't you get it yet?  It's not a Windows problem it's a BIOS problem.  If you can only see one card at a time in BIOS, there's _nothing_ you can do in Windows to solve your problem.  Look in your BIOS for the answer.
 

[acebmxer]

Don't you get it yet?  It's not a Windows problem it's a BIOS problem.  If you can only see one card at a time in BIOS, there's _nothing_ you can do in Windows to solve your problem.  Look in your BIOS for the answer.
 

What is there to get?  How do you know for sure its a bios problem?  I am not say the OP has a bios problem.  I am only familiar with gigabyte bios's.  I have a EP45-udp3p rev. 1.1 and a x58A-ud5.  I have not had to change any setting in the bios to get 2 cards to work.

Maybe the op should say what motherboard he has.

This still could very well be a windows problem and not a bios problem.

[mmartoccia]

Don't you get it yet?  It's not a Windows problem it's a BIOS problem.  If you can only see one card at a time in BIOS, there's _nothing_ you can do in Windows to solve your problem.  Look in your BIOS for the answer.
 

What is there to get?  How do you know for sure its a bios problem?  I am not say the OP has a bios problem.  I am only familiar with gigabyte bios's.  I have a EP45-udp3p rev. 1.1 and a x58A-ud5.  I have not had to change any setting in the bios to get 2 cards to work.

Maybe the op should say what motherboard he has.

This still could very well be a windows problem and not a bios problem.

Thanks guys, I really do appreciate all the help.  I'm leaning towards it being a BIOS/MB issure.  Its highly suspect that I could not get the card realized on boot by the BIOS.  I dont see anything that stands-out in the BIOS that may alter how it sees the cards.  I'm looking for a bios update and not terribly excited about a floppy based solution.  

Here's an older/archived thread with mention of the MB and a potential bios update http://www.evga.com/forumsarchive/tm.asp?m=748392&mpage=1&key=&#748392

And... the PDF of the manual http://www.evga.com/support/manuals/files/133-k8-nf41.pdf

[Supercrit]

I confirm that a 5770(same as 6770) and a 6950 unlocked work together
both doing combined 560~570mh/s bit lower than expected probably due to the 650w PSU
5770 alone does 200 and 6950 alone does near 400

[jh1523]

Don't you get it yet?  It's not a Windows problem it's a BIOS problem.  If you can only see one card at a time in BIOS, there's _nothing_ you can do in Windows to solve your problem.  Look in your BIOS for the answer.
 

What is there to get?  How do you know for sure its a bios problem?  I am not say the OP has a bios problem.  I am only familiar with gigabyte bios's.  I have a EP45-udp3p rev. 1.1 and a x58A-ud5.  I have not had to change any setting in the bios to get 2 cards to work.

Maybe the op should say what motherboard he has.

This still could very well be a windows problem and not a bios problem.

Thanks guys, I really do appreciate all the help.  I'm leaning towards it being a BIOS/MB issure.  Its highly suspect that I could not get the card realized on boot by the BIOS.  I dont see anything that stands-out in the BIOS that may alter how it sees the cards.  I'm looking for a bios update and not terribly excited about a floppy based solution.  

Here's an older/archived thread with mention of the MB and a potential bios update http://www.evga.com/forumsarchive/tm.asp?m=748392&mpage=1&key=&#748392

And... the PDF of the manual http://www.evga.com/support/manuals/files/133-k8-nf41.pdf

That manual has precious little information. The BIOS isn't documented - they say there's a separate PDF for that but I can't find it on EVGA's site.
If it comes to BIOS flashing don't worry about floppies. USB sticks can be made to boot DOS and flashing can be done from there. http://www.bootdisk.com/pendrive.htm

I also use a nforce4-based motherboard for a miner (Asus A8N-SLI premium) and it has a few things that need to be done before it will work with 2 video cards at once. Firstly it has a power connector on the motherboard that needs to have a 4-pin molex plugged in from the power supply (connector like for a hard drive), and secondly there is a setting in BIOS to select between single and dual video card.

Also from your manual it looks like in dual card mode you have to attach the monitor cable to the one that sits in the lower slot (last one before the PCI slots) - are you doing that?

[mmartoccia]

Don't you get it yet?  It's not a Windows problem it's a BIOS problem.  If you can only see one card at a time in BIOS, there's _nothing_ you can do in Windows to solve your problem.  Look in your BIOS for the answer.
 

What is there to get?  How do you know for sure its a bios problem?  I am not say the OP has a bios problem.  I am only familiar with gigabyte bios's.  I have a EP45-udp3p rev. 1.1 and a x58A-ud5.  I have not had to change any setting in the bios to get 2 cards to work.

Maybe the op should say what motherboard he has.

This still could very well be a windows problem and not a bios problem.

Thanks guys, I really do appreciate all the help.  I'm leaning towards it being a BIOS/MB issure.  Its highly suspect that I could not get the card realized on boot by the BIOS.  I dont see anything that stands-out in the BIOS that may alter how it sees the cards.  I'm looking for a bios update and not terribly excited about a floppy based solution.  

Here's an older/archived thread with mention of the MB and a potential bios update http://www.evga.com/forumsarchive/tm.asp?m=748392&mpage=1&key=&#748392

And... the PDF of the manual http://www.evga.com/support/manuals/files/133-k8-nf41.pdf

That manual has precious little information. The BIOS isn't documented - they say there's a separate PDF for that but I can't find it on EVGA's site.
If it comes to BIOS flashing don't worry about floppies. USB sticks can be made to boot DOS and flashing can be done from there. http://www.bootdisk.com/pendrive.htm

I also use a nforce4-based motherboard for a miner (Asus A8N-SLI premium) and it has a few things that need to be done before it will work with 2 video cards at once. Firstly it has a power connector on the motherboard that needs to have a 4-pin molex plugged in from the power supply (connector like for a hard drive), and secondly there is a setting in BIOS to select between single and dual video card.

Also from your manual it looks like in dual card mode you have to attach the monitor cable to the one that sits in the lower slot (last one before the PCI slots) - are you doing that?

Awesome!  Thank you so much for digging in  

Yeah, the bios has very little features in support of multiple cards.   I was able to bring the BIOS to current which did add a couple new features.  However, the only thing it added WRT PCIE was Width (selection of X8 or X16).  Nothing to the point of 1 or 2 video cards.  

Great find on the 4-pin molex!  I did not have this plugged-in.  Even so, it has not changed any recognition of the second card.

I have the cards in the following slots:

Slot 1: 6770 w/ Dummy DVI (I'm using 68ohm resistors as that's what I've read on many sites but I think spec calls for 75ohm)
Slot 3: 6950 w/ Monitor

When IRQ's are allocated by the BIOS on boot, should I see two displays?  I only see the one.

Any additional insights/help would be greatly appreciated!

[jh1523]

Hmm I'm kinda out of ideas. The miner I was talking about is in a basement 2 zipcodes away from here, so I don't have easy access to its BIOS screens. Try setting the PCI-E width to x8 (as it's supposed to be in dual-card mode) and see if that makes a difference. Dunno about IRQs, let me see if I can remotely dig into /proc and find out.

(edit)

Code:

cat /proc/interrupts
   0:         44          0   IO-APIC-edge      timer
   1:          0          8   IO-APIC-edge      i8042
   4:          0          1   IO-APIC-edge
   6:          0          5   IO-APIC-edge      floppy
   7:          1          0   IO-APIC-edge      parport0
   8:          0          0   IO-APIC-edge      rtc0
   9:          0          0   IO-APIC-fasteoi   acpi
  10:          0          0   IO-APIC-edge      MPU401 UART
  14:          5       1837   IO-APIC-edge      pata_amd
  15:      41944    4686121   IO-APIC-edge      pata_amd
  16:          2       4954   IO-APIC-fasteoi   firewire_ohci, HDA Intel
  17:        518     729929   IO-APIC-fasteoi   skge@pci:0000:05:0c.0
  19:          0         27   IO-APIC-fasteoi   HDA Intel
  20:          0          0   IO-APIC-fasteoi   sata_nv
  21:          0          0   IO-APIC-fasteoi   sata_nv
  22:      16499    1593063   IO-APIC-fasteoi   ehci_hcd:usb1, NVidia CK804
  23:          1       1077   IO-APIC-fasteoi   ohci_hcd:usb2
  28:       5941   14654466   PCI-MSI-edge      fglrx[1]@PCI:1:0:0
  29:       6243   17925167   PCI-MSI-edge      fglrx[0]@PCI:2:0:0
 NMI:          0          0   Non-maskable interrupts
 LOC:    6412059    6526522   Local timer interrupts
 SPU:          0          0   Spurious interrupts
 PMI:          0          0   Performance monitoring interrupts
 PND:          0          0   Performance pending work
 RES:    6721607    5782834   Rescheduling interrupts
 CAL:        147        102   Function call interrupts
 TLB:     227829     317605   TLB shootdowns
 TRM:          0          0   Thermal event interrupts
 THR:          0          0   Threshold APIC interrupts
 MCE:          0          0   Machine check exceptions
 MCP:       1051       1051   Machine check polls
 ERR:          1
 MIS:          0

Yes, it looks like each card gets its own interrupt (28 and 29 in the listing above)

68ohm resistors are fine for dummy plugs, but that has nothing to do with the BIOS - it doesn't care if you have monitors attached at all IIRC.