[1 BTC BOUNTY CLAIMED!] Get 6 radeon 7970 installing and mining in Windows

[ISAWHIM]

Just for the record, windows changed something, along with the drivers...

The "registry" fails to hold more than 4x of any single card on win-7(64bit).

The solution, which I did not realize I had done, was to have previously had the v12 ccc drivers. Then, the newer v13 drivers were installed. (Major version numbers are "separate" drivers. As opposed to having 13.1 then 13.3, which is a minor driver change, thus, the same exact driver.) Thus, you can run both separately. 4x per major version. (Might be 4-thread duplication limit? One thread/instance of the drivers per card now. As opposed to one thread trying to control all cards at once.)

Windows rolled-back the driver for me, for two of my cards, as I installed them one at a time. I had not noticed this, as I had disabled the CCC from starting. (Because I use Afterburner to control my cards.)

After spending two days trying to figure out why this was not a working solution (Just adding the cards and using the jumpers), for others... I dug deeper. (For win7-64bit.)

Another thing that was suggested, but I could not get it to work with windows new updates...
Card 1, 2, 3 set in cross-fire mode, with the links (No other cards added at the time of setting-up "Cross-fire" support.)
Use the monitor on the middle-one (the 16x native slot, with the 16x riser)
That causes windows to treat the three cards as "One card", with a slight performance loss in mining. The 16x connection will "re-route" data-channels, only using 8x of them, and not using the ones from the two surrounding 1x slots.)

Then... Add the other cards one at a time, in slots 5, 6, 7... all with the jumpers, and the two above 1,3 also with the jumper, only the one-card on the full 16x riser #2, being without a jumper. (So it can actually do crossfire-mode. 1x will not.) Then dummy-plug card #2, the 16x linked cross-fire main card... and move the monitor to the card in slot #5 or #6, to get the others to be seen, as you add them.

Yes, they should all be seen now, without the /!\ and should all function. Even without the roll-back drivers. (Which should work without doing all this other crap.)

NOTE: It will "seem" like nothing is happening... The cards have a hell of a long time trying to "activate" and figure out which ones to display an image on. Takes about a minute to see anything on the screen on "rebooting" or "start-up", but eventually one screen on #5 or #6 should come-on... But I never shut them down anymore, so I forget about this every time I reboot... kind-of scares me into thinking that I fried something.

If it still does not work for you... Then you MUST use win-8 or Linux. (I have to test my "vista 32bit", I don't have vista 64-bit to test on.)

Funny thing... win7 shows only one monitor per card, in the settings. In vista/xp the monitor setup shows all 4 monitors per card. EG, 6-cards = 24-monitors available to configure. (This may also have something to do with win-7 new "limitation", as they are degrading crap to make win-8 sell. Just like they did with xp/vista... but they stopped degrading most of xp/vista.... Which may be why the stuff still functions there. for now. Stop auto-updates. hehe.)

[svetlim]

Oh ya bunch of whiners.

Tip away: 1BXNapSrzTSfmqSD63e49eh2JvDkeotCxt

It basically comes down to a limitation of Windows 7. What the specific limitation is, I don't know. But Windows 8 allows 1 more GPU to be detected and mineable. So if you install 13.1 driver on win7 and get 4 GPU working, you will get 5 GPU working on win8. Win8 is also annoying though in that you can't install "older" drivers, some of which allow an additional GPU mineable on top of that. The catalyst installer manager simply won't show the display driver installer option. SO. Here we go.

Install windows 8.
Wipe any previous GPU drivers off with amd_cleanup_util_1.2.1.0.exe (google it) if you have installed them before.
Install 13.1 plus OpenCL included with it. Personally, I only installed display driver, opencl sdk, and the hdmi driver because I dont like seeing stuff without drivers. None of the other stuff is required.
You will now have 5 GPU working with one with an error code 43 inside the Device Manager.
Open 12.6 and install only to the point where it extracts stuff into C:\AMD\Support\. Do not actually install drivers. We just need to extract.
In device manager, right click the errored GPU -> Properties -> Driver tab -> Update Driver -> Browse my computer for driver software -> Let me pick from a list of device drivers on my computer -> Have Disk -> Browse -> Navigate to C:\AMD\Support\12-6_vista_win7_64_dd_ccc_whql\Packages\Drivers\Display\W76A_INF and select either .inf file (it doesn't seem to make a difference) -> OK -> Should only have one device listed under "Model". Hit Next.

It should now proceed to downgrade from 13.1 to 12.6, which is the highest version driver that allows an extra GPU. You screen may flicker MANY times, and your device manager may appear to freeze/hang. Just let it do it's thing. It may take upwards of an hour or longer. You may get a BSOD too. Just go with it. If you're coming on 2 hours or longer, try doing a hard reset. You -should- now have all 6 GPU installed OK in device manager and detected in OpenCL. If not, reboot again (just in case).

If this doesn't work, well, I don't know what to say. This is just the solution I was given. (Well, actually, I was recommended the special 7970 release driver, but I was worried it wouldnt work with 13.1 opencl)

Tips: 1BXNapSrzTSfmqSD63e49eh2JvDkeotCxt

all b..... are from Microsoft. 10x for solution. before 2-3 week I have same problem and with Win8 only work 5 GPUs.

[nullspot]

You will now have 5 GPU working with one with an error code 43 inside the Device Manager.
Open 12.6 and install only to the point where it extracts stuff into C:\AMD\Support\. Do not actually install drivers. We just need to extract.
In device manager, right click the errored GPU -> Properties -> Driver tab -> Update Driver -> Browse my computer for driver software -> Let me pick from a list of device drivers on my computer -> Have Disk -> Browse -> Navigate to C:\AMD\Support\12-6_vista_win7_64_dd_ccc_whql\Packages\Drivers\Display\W76A_INF and select either .inf file (it doesn't seem to make a difference) -> OK -> Should only have one device listed under "Model". Hit Next.
It should now proceed to downgrade from 13.1 to 12.6, which is the highest version driver that allows an extra GPU. You screen may flicker MANY times, and your device manager may appear to freeze/hang. Just let it do it's thing. It may take upwards of an hour or longer. You may get a BSOD too. Just go with it. If you're coming on 2 hours or longer, try doing a hard reset. You -should- now have all 6 GPU installed OK in device manager and detected in OpenCL. If not, reboot again (just in case).

Can anyone else confirm they've been able to do this step? the manual selection of the 12.6 driver? I've got win8 working with 5 gpus, and the last slot with the error 43, just the same. But when I attempt to select the 12.6 driver following these exact instructions, I'm told by windows that I can't use that driver because it is not compatible with this version of windows...

[BlazinBeaches]

You will now have 5 GPU working with one with an error code 43 inside the Device Manager.
Open 12.6 and install only to the point where it extracts stuff into C:\AMD\Support\. Do not actually install drivers. We just need to extract.
In device manager, right click the errored GPU -> Properties -> Driver tab -> Update Driver -> Browse my computer for driver software -> Let me pick from a list of device drivers on my computer -> Have Disk -> Browse -> Navigate to C:\AMD\Support\12-6_vista_win7_64_dd_ccc_whql\Packages\Drivers\Display\W76A_INF and select either .inf file (it doesn't seem to make a difference) -> OK -> Should only have one device listed under "Model". Hit Next.
It should now proceed to downgrade from 13.1 to 12.6, which is the highest version driver that allows an extra GPU. You screen may flicker MANY times, and your device manager may appear to freeze/hang. Just let it do it's thing. It may take upwards of an hour or longer. You may get a BSOD too. Just go with it. If you're coming on 2 hours or longer, try doing a hard reset. You -should- now have all 6 GPU installed OK in device manager and detected in OpenCL. If not, reboot again (just in case).

Can anyone else confirm they've been able to do this step? the manual selection of the 12.6 driver? I've got win8 working with 5 gpus, and the last slot with the error 43, just the same. But when I attempt to select the 12.6 driver following these exact instructions, I'm told by windows that I can't use that driver because it is not compatible with this version of windows...

My first try I didn't have success.  It was after a fresh reformat that it worked.  It definitely works.  You'll know it's doing it's thing when the monitor starts blinking continuously for about 10 minutes.  After that it's good to go, and surprisingly this method is much more stable on my system.  The latest beta drivers would give artifacts and I had to lower the intensity on the main card, now I can go full intensity on all cards, get full speed, higher speed than before, and do things in windows without any probs.

[ElJay]

I tried this method and eventually managed to succeed. But for some odd reason windows 8 reverses the 12.6 driver installation and error 43 appears again.. After this I can reinstall the driver but after a couple hours the same shit happens again. Pain in the ass lol. Does anyone know why this is happening?

I'm also experimenting with a litecoin version of BAMT at the moment but it only starts up with 5 GPU. When I add the 6th one it simply gives a blank screen after startup.. =/

[ssateneth]

You will now have 5 GPU working with one with an error code 43 inside the Device Manager.
Open 12.6 and install only to the point where it extracts stuff into C:\AMD\Support\. Do not actually install drivers. We just need to extract.
In device manager, right click the errored GPU -> Properties -> Driver tab -> Update Driver -> Browse my computer for driver software -> Let me pick from a list of device drivers on my computer -> Have Disk -> Browse -> Navigate to C:\AMD\Support\12-6_vista_win7_64_dd_ccc_whql\Packages\Drivers\Display\W76A_INF and select either .inf file (it doesn't seem to make a difference) -> OK -> Should only have one device listed under "Model". Hit Next.
It should now proceed to downgrade from 13.1 to 12.6, which is the highest version driver that allows an extra GPU. You screen may flicker MANY times, and your device manager may appear to freeze/hang. Just let it do it's thing. It may take upwards of an hour or longer. You may get a BSOD too. Just go with it. If you're coming on 2 hours or longer, try doing a hard reset. You -should- now have all 6 GPU installed OK in device manager and detected in OpenCL. If not, reboot again (just in case).

Can anyone else confirm they've been able to do this step? the manual selection of the 12.6 driver? I've got win8 working with 5 gpus, and the last slot with the error 43, just the same. But when I attempt to select the 12.6 driver following these exact instructions, I'm told by windows that I can't use that driver because it is not compatible with this version of windows...

I can confirm this because I've done it myself

If you are using a video card that absolutely requires a later driver revision (such as the 7870 XT/Myst edition is my guess), it will be impossible for you to find a solution for 6 gpu in windows. You will need to go linux i guess.

[Lucko]

Oh ya bunch of whiners.

Tip away: 1BXNapSrzTSfmqSD63e49eh2JvDkeotCxt

It basically comes down to a limitation of Windows 7. What the specific limitation is, I don't know. But Windows 8 allows 1 more GPU to be detected and mineable. So if you install 13.1 driver on win7 and get 4 GPU working, you will get 5 GPU working on win8. Win8 is also annoying though in that you can't install "older" drivers, some of which allow an additional GPU mineable on top of that. The catalyst installer manager simply won't show the display driver installer option. SO. Here we go.

Install windows 8.
Wipe any previous GPU drivers off with amd_cleanup_util_1.2.1.0.exe (google it) if you have installed them before.
Install 13.1 plus OpenCL included with it. Personally, I only installed display driver, opencl sdk, and the hdmi driver because I dont like seeing stuff without drivers. None of the other stuff is required.
You will now have 5 GPU working with one with an error code 43 inside the Device Manager.
Open 12.6 and install only to the point where it extracts stuff into C:\AMD\Support\. Do not actually install drivers. We just need to extract.
In device manager, right click the errored GPU -> Properties -> Driver tab -> Update Driver -> Browse my computer for driver software -> Let me pick from a list of device drivers on my computer -> Have Disk -> Browse -> Navigate to C:\AMD\Support\12-6_vista_win7_64_dd_ccc_whql\Packages\Drivers\Display\W76A_INF and select either .inf file (it doesn't seem to make a difference) -> OK -> Should only have one device listed under "Model". Hit Next.

It should now proceed to downgrade from 13.1 to 12.6, which is the highest version driver that allows an extra GPU. You screen may flicker MANY times, and your device manager may appear to freeze/hang. Just let it do it's thing. It may take upwards of an hour or longer. You may get a BSOD too. Just go with it. If you're coming on 2 hours or longer, try doing a hard reset. You -should- now have all 6 GPU installed OK in device manager and detected in OpenCL. If not, reboot again (just in case).

If this doesn't work, well, I don't know what to say. This is just the solution I was given. (Well, actually, I was recommended the special 7970 release driver, but I was worried it wouldnt work with 13.1 opencl)

Tips: 1BXNapSrzTSfmqSD63e49eh2JvDkeotCxt

Just notice this post. I think win8 part is not necessary. I got 8 GPUs on win7 using this proces that I figure out too about 3 weeks ago. But they were not all 7970 cards... But I have 6 cards pluged in with 8 GPU total on win7. Works without a problem...

[debeliamark]

Oh ya bunch of whiners.

Tip away: 1BXNapSrzTSfmqSD63e49eh2JvDkeotCxt

It basically comes down to a limitation of Windows 7. What the specific limitation is, I don't know. But Windows 8 allows 1 more GPU to be detected and mineable. So if you install 13.1 driver on win7 and get 4 GPU working, you will get 5 GPU working on win8. Win8 is also annoying though in that you can't install "older" drivers, some of which allow an additional GPU mineable on top of that. The catalyst installer manager simply won't show the display driver installer option. SO. Here we go.

Install windows 8.
Wipe any previous GPU drivers off with amd_cleanup_util_1.2.1.0.exe (google it) if you have installed them before.
Install 13.1 plus OpenCL included with it. Personally, I only installed display driver, opencl sdk, and the hdmi driver because I dont like seeing stuff without drivers. None of the other stuff is required.
You will now have 5 GPU working with one with an error code 43 inside the Device Manager.
Open 12.6 and install only to the point where it extracts stuff into C:\AMD\Support\. Do not actually install drivers. We just need to extract.
In device manager, right click the errored GPU -> Properties -> Driver tab -> Update Driver -> Browse my computer for driver software -> Let me pick from a list of device drivers on my computer -> Have Disk -> Browse -> Navigate to C:\AMD\Support\12-6_vista_win7_64_dd_ccc_whql\Packages\Drivers\Display\W76A_INF and select either .inf file (it doesn't seem to make a difference) -> OK -> Should only have one device listed under "Model". Hit Next.

It should now proceed to downgrade from 13.1 to 12.6, which is the highest version driver that allows an extra GPU. You screen may flicker MANY times, and your device manager may appear to freeze/hang. Just let it do it's thing. It may take upwards of an hour or longer. You may get a BSOD too. Just go with it. If you're coming on 2 hours or longer, try doing a hard reset. You -should- now have all 6 GPU installed OK in device manager and detected in OpenCL. If not, reboot again (just in case).

If this doesn't work, well, I don't know what to say. This is just the solution I was given. (Well, actually, I was recommended the special 7970 release driver, but I was worried it wouldnt work with 13.1 opencl)

Tips: 1BXNapSrzTSfmqSD63e49eh2JvDkeotCxt

Just notice this post. I think win8 part is not necessary. I got 8 GPUs on win7 using this proces that I figure out too about 3 weeks ago. But they were not all 7970 cards... But I have 6 cards pluged in with 8 GPU total on win7. Works without a problem...

For sure - 8 x RV870 - presented single in HD5870 or doubled in 5970 is possible to run under Windows x64 ( not a problem Vista /7 or 8 ... my own run at 7 Pro ) and for sure is not easy to make more that 5 Thaiti GPU cores ( HD79x0 ) to work together ... i was place max 6x with trick 13.1 back to 12.6 and 5x if install 12.8 and back to 12.6 ... so - all is depend of drivers ... same was and early with 3 x 5970 when Win7 do not want to catch 6-th core ... and BlueScreenofDead but ... who search - will find solution finaly.

Just my 2 cents...

P.S. 5 x 7970 over middle range MB + AMD X6 CPU + PSU high class ( 1200 Corsair or ... my favorite 1250 Enermax ) is exactly the best monster.
P.S.2 - no need to place any CrossFireX, TriFireX ect... jumpers ...

[DiamondHunter]

All right,
Here is the solution for the 6x7950 on Windows.

Recently I built 2 systems with Z77A-GD65 MB and MSI TwinFrozr 7950 GPUs. No issues whatsoever. Installed Windows 8, Catalyst 13.1 and bang, I had all 6 GPUs up and running.

Then couple of weeks later I had the same components for two more rigs. Used the same steps as before, but could not get the 6th GPU to show up.(the error code 43 issue) Tried multiple times re-installing Win8, Win7. And probably tried every possible catalyst driver..... No luck.

Just by luck I was at one of the good rigs, and noticed the Catalyst installer on the desktop.... Then it hit me..... After some comparison and digging, I found out that the Catalyst 13.1 installer on the problem rigs was different from the 13.1 installer on the first two rigs. No friggin way....

Well, copied over to the two new systems the 13.1 installer from the good running machines, and voila half an hour later I got two more rigs with 6 GPUs all set up.


So after reading all this crap I dumped on you , here is the good part:

Go and download the 13.1 catalyst from Guru3d.com and techpowerup.com. Here is the result. The third file on the image is the one that worked on all my rigs.  

https://www.dropbox.com/s/z08mvvjz1tccpk6/Catalyst%2013.1%20Differences.JPG

Get the 13.1 from techpowerup.com and you are all set.
Here is the working 13.1 installer that I used for comparison: https://www.dropbox.com/s/1hoxkz0y8fe933g/13-1_vista_win7_win8_64_dd_ccc_whql%20Working.exe

With that, 6 GPUs on Windows 8 setup is a smooth sail.
 

[lbr]

wow.

Indeed, TechPowerUp 13.1 is different from 13.1 from AMD, looks like techpowerup's version is older.
CH 151 592.inf vs CH 154 961.inf
ofc if those numbers actually mean anything ; )

Differences both in the driver and opencl packages.
edit: though OpenCL msi's are different, but contents is the same.

+edit: differences are only in the .inf files(for driver), so it may be configuration(registry) related

[lbr]

So.. DiamondHunter, are you willing to screw up your rig? ; )
And to pinpoint which registry setting is it.



C7151592.inf
HKR,, DP_DisableHBR2,             %REG_DWORD%, 1

HKLM,"Software\ATI Technologies\CBT",ReleaseVersion,,"9.012-121219a-151592C-ATI"
HKR,, ReleaseVersion,,"9.012-121219a-151592C-ATI"

HKR,, DalNumOfPathPerDpMstConnector, %REG_DWORD%, 0

HKR,, PX_AI_IndInstallSupport, %REG_DWORD%, 1


vs


C7154961.inf
HKR,, DP_DisableHBR2,             %REG_DWORD%, 0

HKLM,"Software\ATI Technologies\CBT",ReleaseVersion,,"9.012-121219a-154961C-ATI"
HKR,, ReleaseVersion,,"9.012-121219a-154961C-ATI"

HKR,, DisableMMSnifferCode,               %REG_DWORD%,    0

HKR,, PX_AI_IndInstallSupport

HKR,, DalNumOfPathPerDpMstConnector

[BlazinBeaches]

Does anyone else's GPU in the shorted presence pin slot run hotter than the rest?  Mine in the one slot runs 8-10C hotter than all the other cards, including the cards in the very middle.  The cards are exact same and are all equally spaced apart.  It even runs 5C hotter than the card that is directly above the CPU heatsink.

Not a big deal as I undervolt a bit, just curious

[DiamondHunter]

So.. DiamondHunter, are you willing to screw up your rig? ; )
And to pinpoint which registry setting is it.

Will take a look and let you know guys.

[lbr]

Does anyone else's GPU in the shorted presence pin slot run hotter than the rest?  Mine in the one slot runs 8-10C hotter than all the other cards, including the cards in the very middle.  The cards are exact same and are all equally spaced apart.  It even runs 5C hotter than the card that is directly above the CPU heatsink.

Not a big deal as I undervolt a bit, just curious

cmon, swap them and check..
also 'equally spaced apart' does not matter unless you thermally isolate them from each other.
and the one above the cpu heatsink theoretically should be cooler a bit, cause cpu heatsink will suck hot air from that card, assuming you have stock heatsink.

[BlazinBeaches]

Does anyone else's GPU in the shorted presence pin slot run hotter than the rest?  Mine in the one slot runs 8-10C hotter than all the other cards, including the cards in the very middle.  The cards are exact same and are all equally spaced apart.  It even runs 5C hotter than the card that is directly above the CPU heatsink.

Not a big deal as I undervolt a bit, just curious

cmon, swap them and check..
also 'equally spaced apart' does not matter unless you thermally isolate them from each other.
and the one above the cpu heatsink theoretically should be cooler a bit, cause cpu heatsink will suck hot air from that card, assuming you have stock heatsink.

I'm not swappin, my cards are bolted down and in a sealed box ducted to the window.  If it was a big deal I would test it, but as I already said, it's not and this was mere conversation on the subject.

Come to think of it though, the card that is in that slot was previously plugged into slot 6 while in the exact same position and it didn't run hot like it is now.  And the cards around it were still in the same spots.

And same spacing per card does matter.  6 cards with .5 inches in between vs 6 cards with 2 inches between have a clear temperature difference.  I only mentioned that to null the idea of people coming in here and suggesting it.

Thermal isolation is useful in many situations but I have dual 600cfm fans centered covering every parameter of the cards including underneath the mobo.  So in this case it may or may not offer a few C temperature drop. The temps are great already so it's not an issue.

Temps on 4 of the cards are within 2C of each other, with the exception of the card in the slot of question, and the card above the CPU only when the chip is at full load.  Which yes does make sense as the fan is driving air towards the cpu which in turn causes some of that air to be blown right back up through the fan.  The silverstone air penetrator videos provide some good examples of the large amount of air that gets pushed back through computer fans when any kind of resistance is on the receiving end.

[ssateneth]

Dunno why people are still going back and forth about this. I posted the solution for this already. It works for 7970, 7950, 7870 (non-xt, non-myst), 7850, 7770, 7750.

[lbr]

So.. DiamondHunter, are you willing to screw up your rig? ; )
And to pinpoint which registry setting is it.

Will take a look and let you know guys.

I've installed those 13.1 drivers from techpowerup on my 6gpu rig and it works ; )

Windows 2008 R2, Catalyst 13.1 from techpowerup(driver only), 2x6950, 4x7950 - works
Windows 2008 R2, Catalyst 13.1 from AMD(driver only), 2x6950, 4x7950 - does not work
Windows 2008 R2, Catalyst 12.6 from AMD(driver only), 2x6950, 4x7950 - works

I'm pretty sure Windows 7 will work too.

[lbr]

Dunno why people are still going back and forth about this. I posted the solution for this already. It works for 7970, 7950, 7870 (non-xt, non-myst), 7850, 7770, 7750.

You do understand that so called 'your solution' is a bit weird.. I mean.. install win8, install 13.1, replace it with 12.6.. that's crap)
I've been runnning 6gpu rig without any issues with just clean w2k8 install+12.6 that's all, no win8 no drivers updating..
But now we have 13.1 working for 6GPU rigs, and I hope soon we will have any Catalyst version working for 6GPU rigs.

[heartofalion]

All right,
Here is the solution for the 6x7950 on Windows.

Recently I built 2 systems with Z77A-GD65 MB and MSI TwinFrozr 7950 GPUs. No issues whatsoever. Installed Windows 8, Catalyst 13.1 and bang, I had all 6 GPUs up and running.

Then couple of weeks later I had the same components for two more rigs. Used the same steps as before, but could not get the 6th GPU to show up.(the error code 43 issue) Tried multiple times re-installing Win8, Win7. And probably tried every possible catalyst driver..... No luck.

Just by luck I was at one of the good rigs, and noticed the Catalyst installer on the desktop.... Then it hit me..... After some comparison and digging, I found out that the Catalyst 13.1 installer on the problem rigs was different from the 13.1 installer on the first two rigs. No friggin way....

Well, copied over to the two new systems the 13.1 installer from the good running machines, and voila half an hour later I got two more rigs with 6 GPUs all set up.


So after reading all this crap I dumped on you , here is the good part:

Go and download the 13.1 catalyst from Guru3d.com and techpowerup.com. Here is the result. The third file on the image is the one that worked on all my rigs.  

https://www.dropbox.com/s/z08mvvjz1tccpk6/Catalyst%2013.1%20Differences.JPG

Get the 13.1 from techpowerup.com and you are all set.
Here is the working 13.1 installer that I used for comparison: https://www.dropbox.com/s/1hoxkz0y8fe933g/13-1_vista_win7_win8_64_dd_ccc_whql%20Working.exe

With that, 6 GPUs on Windows 8 setup is a smooth sail.
 

Sweet Mary, mother of god! If this has fixed my stability issue you are my favorite person on the internet right now! I did the 12.6 setup above and it was stable for a while but i had to redo some drivers (drivers kept crashing turned out to be a powered riser issue). Did the 12.6 hack again but must have did it differently because the rig was really spotty after that.

Just did these 13.1 drivers all 5 7950's showed up in windows 7 and first run in cgminer and it has been up for 15 minutes (doesnt sound like much but i was struggling to make it that long before). If this corrected the issue, you my friend are a godsend!

[bondar]

suggested 13.1 driver works with my win7-64 5x7870 setup! Thank you!
All others except old 12.6 failed to run 5-th GPU.