Hello!

Sorry for the broken English!

Graphics Cards:

MSI Radeon HD 7770 - R7770-2PMD1GD5/OC

Asus Radeon HD7770 - HD7770-DC-1GD5-V2

AMD Catalyst Driver Version- 12.8. Also tried all drivers launched in the past 2 months

Operating System: Windows 7 64-bit Ultimate

Issue Details: Every time I want to enable or disable Crossfire X from the Catalyst Control Center the system freezes and a hard reset is the only option. I can only enable or disable Crossfire X if I perform a clean install of the AMD driver. After the fresh install I can enable or disable Crossfire only once. After this any other attempt to enable or disable it results in system freeze and hard reset is required. The system runs fine with either of the cards installed  and I have tested both of them for overheating or other issues and I have not been able to find any problems. It does not matter which card is installed in which PCI-E slot, the problem is the same. The cards are not and have never been overclocked.

Another problem is that while Crossfire X is enabled DOTA 2 will not work. The game freezes after about 10 minutes of gameplay. This is not such a big problem since it runs perfectly with only one card but not beeing able to enable or disable Crossfire stops me from playing the game without performing a clean driver install.

Another issue is that while Crossfire is enbaled, Firefox becomes unusable after 1-2 minuted of browsing. The screen turns black or becomes heavely pixelated but only in the Firefox window, the rest of the system functions correctly.  Closing and reopening Firefox solves the problem but only for a few minutes. This issue has made istelf aparent in several versions of Firefox I have tried. It would not bee a problem if I could enable Crossfire only while I playh certain high demanding games.

System Specs:

Motherboard: AsRock Z77 Extreme4

CPU: Intel Core i5 3570K @ 4.2 Ghz, 1.240V, x42 multiplier

RAM: G.Skill RipjawsX 4GB DDR3-2133mhz 9-11-9-28

PUS: Corsair HX-750W

Display Devices: Samsung Syncmaster 2243NW connected using a VGA cable

Motherboard Bios: AsRock 2.20

No other PCI-E or PCI cards are currently installed.

The system has been tested for Overclock stability with Prime 95 and Intel XTU and has passed 8 hour long stress test.

Both GPUs have been tested on a Uniger Heaven 3.0 loop, and both have passed without any problems both individually and with Crossfire Enabled. No problems are aparent in high-demanding games ( Crysis 2, Metro 2033, Skyrim) while Crossfire is enabled. Performance in these games and in the benchmark is more that satisfactory while Crossfire is enabled. Temperatures for both CPU and GPu have been well into acceptable parameters. No blue-screens or system freezes have happened during the stress tests.

I hope there is a solution for my inability to turn Crosfire On or Off. I am currently using only one card because of these problems.

Thank You!

Generally speaking I am not a big proponent of trying to CrossFire/SLi graphics cards that are made by different manufacturers.  You never know for sure if they have done something that breaks from the reference standard which could possibly cause odd behavior.

Specifically with these two cards, did you notice that the memory frequency  is different?  That could cause problems when you enable/disable CrossFire.  Have you attempted to make the frequecies match before you enable it?

http://www.newegg.com/Product/Product.aspx?Item=N82E16814127664R <--Effective Memory Clock = 1125MHz

http://www.newegg.com/Product/Product.aspx?Item=N82E16814121632R <--Effective Memory Clock = 1150MHz

The opinions expressed above do not represent those of Advanced Micro Devices or any of their affiliates.
Requiescat In Pace AMD Processor Forums | Member since: 1/19/2009 | Post count: 4142
Please don't PM me with questions, instead create a thread so that everyone can assist and benefit from the knowledge provided. Thanks in advance!

I may not be an exprt in such things but I do know that mismatching manufacturers should not be a problem. I tried your suggestion and the result is the same. You argument that  manufacturers break from standard reference is not valid in my opinion. PCB design, Core clock, memory Clock, cooling design should not create any problems as long as the GPU core is the same. Crossfire should work without any problem as long as you have 2 cards with the same core.

If what you say is true and mismatching manufacturers is not recomended then why does AMD not strictly specify this for their GPUs? Nowhere on AMD's product description of the HD 7770 does it say that Crossfire will work fine ONLY if you have 2 identical cards from the same manufacturers.

The reference design is supplied to the manufacturers.  That doesn't mean that they are not at liberty to choose components that stray from what AMD recommended.  For instance, you can buy a 2GB version of a card and perhaps they also sell a 3GB variant, they are both the same model card though....as you put it, the same GPU core, but that does not guarantee that the cards are compatible to be ran in CrossFire. 

The same can be said for NVidia, I have a friend that purchased two GTX580's....one was a 3GB memory card, the other a 6GB memory card....they would not SLi together even though they were manufactured by the same company.

Something that you can look for on the PCB right above the copper contact point for the PCIe connector is to see if both cards have AMD's logo/name stamped on there....if you see the card manufacturer's logo/name stamped there, or simply see no AMD name/logo, then that means that that card is not a reference design....as per my examples below, both are AMD 7770 cards with the same GPU core:

Reference: http://images.anandtech.com/doci/5541/7770.jpg

Non-reference: http://img.hexus.net/v2/graphics_cards/amd/MSI/R7770/CoolerS.jpg

Aside from all of that, one of the reasons why people will flash their graphics card BIOS is to force them to match in their BIOS version, which in many cases is the only way that some individuals can get CrossFire/SLi to work, using programs such as Nibitor to modify settings to allow for better functionality.

Edit:

Your MSI 7770 is not reference per the link below and most likely the reason why you have problems with the cards....the BIOS on the MSI card must vary enough from the ASUS one that it is causing problems.

http://hexus.net/tech/reviews/graphics/35417-msi-radeon-hd-7770-oc-crossfire-examination/

Double edit:

Your ASUS card is also not reference....double whammy....I looked at the image of the back of the card and it has ASUS stamped on the pcb, as per the link below:

http://www.newegg.com/Product/Product.aspx?Item=N82E16814121632

The opinions expressed above do not represent those of Advanced Micro Devices or any of their affiliates.
Requiescat In Pace AMD Processor Forums | Member since: 1/19/2009 | Post count: 4142
Please don't PM me with questions, instead create a thread so that everyone can assist and benefit from the knowledge provided. Thanks in advance!

That is truly sad. I've had 3 SLI systems before with mismatched cards, different PCB's, different BIOS's, different memory buffer and never had problems like these. First AMD GPU so far in my life and by the looks of thing the last one.

I've seen threads all over the place where people complain about not being able to CF/SLi their cards that are made by different manufacturers, feel free to search....overclock.net or xtremesystems.org which are two really big computer tech sites. The thing that has always confused me was why buy two of the same card from two different manufacturers? Aside from availability issues, I just don't understand it. In your case, at least you didn't purchase two really high-end models that cost a lot more.

The opinions expressed above do not represent those of Advanced Micro Devices or any of their affiliates.
Requiescat In Pace AMD Processor Forums | Member since: 1/19/2009 | Post count: 4142
Please don't PM me with questions, instead create a thread so that everyone can assist and benefit from the knowledge provided. Thanks in advance!

I couldn't get a friend's nVidia cards to SLI on his old system, one was a Gigabyte, the other an XFX .. they just wouldn't play together at all .. and I do this for a living. So yes, it can and does happen with nVidia cards too !!

Had another buddy who had x2 HD4870s from Sapphire and HIS and they wouldn't play nice together at all either .. took his HIS out, replaced it with one of our other friend's Sapphire HD4870 and voila .. no issues.

Canis is right here, it's probably down to the different VBIOSes and/or reference/non-reference thing going on .. I'd wager that if both were reference cards there probably wouldn't be a problem.

AM3 965BE / Corsair H70 / 4Gb Corsair XMS3 2000Mhz / GigaByte 990FXA-UD5 / Corsair Force3 90Gb / x2 HD3870 Atomic Edition / x4 1Tb Storage & Momentus XT 250Gb / Sony AD-7700 DVD-RW / Auzen X-Mystique / Enermax INFINITI 650W / Lian-Li PC-7FNWB / Logitech X-530 / Logitech KBoard & MX620 / Logitech C525 / Epson RX685 / DELL U2312HM