6870 Crossfire and ASUS MoBo Problems

saphira928

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I have 2 new XFX Radeon HD 6870 graphics cards in my new ASUS P8P67-M Pro motherboard. They are in the first 2 PCIe x16 slots (navy blue and white) and are connected with a Crossfire bridge. My computer dual boots into both Windows 7 64-bit and Mac OS X Snow Leopard 1.6.8. In both Windows and OS X, both graphics cards are recognized as present in the system, but the first graphics card is running at x16 mode while the second is running at x1 mode. Catalyst Control Center (CCC) in Windows 7 recognizes the first graphics card as the "Primary Adapter" and the second card as the 'Disabled Adapter." 1 monitor is attached to the top DVI port of the first graphics card. When I attach a monitor to the second graphics card, it is not recognized and doesn't work. CCC doesn't show a crossfireX or crossfire tab or options.

I want to make my 2 graphics cards run in x8 and x8 mode in crossfire in Windows 7, and I want each to run 1 monitor in OS X. I noticed that there is an option for the third, black PCIe x16 slot (that I am not using) in the UEFI. When I turn that option to x4, the second graphics card isn't recognized at all (it doesn't appear in Hardware Manager). When I turn it to x2, it appears, but doesn't crossfire or support monitors (the situation I described above).

Please help my fix this problem. How do I force to motherboard to utilize each graphics card in x8 mode? In the motherboard manual it says that it it possible (and preferable) to do this. Why does the configuration of the third, unused PCIe x16 slot matter? Why does CCC not show crossfire options?

Thanks in advance for your help!

- Patrick
 
Just to determine both cards are, in fact, functioning... Have you swapped the video cards (plugged the 2nd into the first slot and the first into the second slot) and then plugged the monitor into the card in the first slot?

Also, anytime you make a physical change to a crossfire setup, you have to 'express' uninstall/re-install the drivers. Do this as well after you make the change above. Your crossfire performance will be inconsistent or non-existent if you don't do this every time you make a physical change to the configuration (even booting with the crossfire connector on or off).

Also, you shouldn't have to manually configure the slot speeds on the PCIe. They will adjust based on what you have plugged into the board.

What make/model power supply do you have?

If you have good and enough power and if you do the swap and the monitor doesn't work through the second card, you can conclude the card the monitor is plugged into is bad. Return it.
 

saphira928

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I have tried my setup with each card in the top PCIe slot and nothing in the remaining slots, and with only 1 monitor plugged in. Everything works fine. When I add the second card (regardless of which card is in the first slot and which is in the second), my computer recognizes the second card in x1 mode and as a disabled adapter. Therefore, I'm pretty sure that there is nothing wrong with the graphics cards.

According to my motherboard manual, it is supposed to auto-recognize the cards as x8 and x8. I contacted ASUS last night about this problem, and I should get an answer by tomorrow night.

I have a Corsair TX750W, which should be more than enough for 1 mobo, 1 i-5, 4x4GB Ram, 2 HDD, and 2 GPU. I have 5 case fans as well, but I haven't connected any of them yet.

I'm interested in your comment about the drivers. What I did was install both new cards into a new build without a crossfire bridge and installed Windows 7. Then I added the bridge and installed the 11.8 drivers. However, THERE ARE NO CROSSFIRE TABS OR OPTIONS VISIBLE IN CATALYST CONTROL CENTER (CCC). Because of this, I can't crossfire my cards. How do I make these options appear in CCC?

Maybe I should uninstall all AMD drivers, run Driver Sweeper and reinstall the drivers. I will try that tomorrow night, once AMD and ASUS get back to me.

Thanks for your help. I really appreciate it.

- Patrick
 

frankthetank909

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Seems to me the board is working fine:

Multi-GPU Support

Supports AMD Quad-GPU CrossFireX™ Technology



Expansion Slots

1 x PCIe 2.0 x16 (blue)
1 x PCIe 2.0 x16 (x4 mode, black)
1 x PCIe 2.0 x1
1 x PCIe x1

thats from your boards page. it seems to me you have 4 PCIE lanes available:

1x 16x
1x 4x
2x 1x

So when you Plug a card into Slot 1 and 3 both cards will operate a 4x mode for xfire

if you plug a car dinto three all three cards operate at 1x speed and the same with the fourth slow...the detection error is your using the wrong pcie slot

try using the first and 3rd slot

or the 1st 16x and the black slot ( which should be 4x) then try it.
 

I hope the driver uninstall/re-install does it for you. Make sure you choose the 'Express Uninstall...' option from the Add/Remove programs menu for Catalyst Control Center.

One thing to note... I know on some implementations of the P67 chipset, the USB 3.0 and SATA III controllers will borrow lanes from your PCIe bus. Are your hard drives plugged into any SATA III (6GB) ports? Do you have any devices plugged into your USB 3.0 ports?

If so (with the computer off of course), plug your disk into the SATA II (3.0GB) and your USB devices in the USB 2.0 ports. Then boot up and see what you get.
 

saphira928

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Jul 16, 2011
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To ubercake:
That could be it! I have 2 WD Caviar Black 750GB 64MB Cache 6GB/s Hard Drives plugged in. 1 is plugged into the 6gb/s marvel controlled slot, and 1 is plugged into the intel 6gb/s slot. I'll try all of these solutions tonight and get back to you tomorrow night, by which time ASUS and AMD should have responded to my help requests. Thank you so much!

To Frank the Tank:
Thanks for your research. However, I think you're looking at the manual wrong (or at the wrong manual). My ASUS P8P67-M PRO has 4 PCIe slots. The first is PCIe x16 and is navy blue. The second is PCIe x1 and is navy blue. The third is PCIe x16 and is white. The fourth is PCIe x16 and is black. My first graphics card is in the first PCIe and my second graphics card is in the third PCIe. According to my manual, the black PCIe, although having a x16 size, can only operate at either x2 or x4. There is an option in the UEFI to switch from x2 mode to x4 mode. At x4 mode, my second graphics card isn't recognized in hardware manager. At x2 mode, it is recognized, but is called a "disabled adapter" in CCC and only runs at x1 mode. I think that this is very odd because neither of my graphics cards are plugged into the black PCIe, and thus the mode really shouldn't make a difference. According to my manual, when using 2 graphics cards, they should be plugged into the navy blue and white PCIe x16 slots "to get better performance." According to the table in the manual, dual graphics cards should run at x8 and x8 mode if they are in these slots. They can also run at x16 and x4 mode if the second card is in the black slot.

To both:
I'm inclined to think that ubercake's explanation of shared SATA III and PCIe bus memory is the correct one. Do either of you know if the problem would be avoided if I only used 1 hard drive, and I plugged it into the Marvel SATA III port rather than the Intel ports? By which I mean: Are either the Marvel or the Intel SATA III ports independent of the PCIe buses?

Thanks again for all of your help! I'll post again tomorrow.

- Patrick