Bitcoin Forum

I have 4 7850's running on a board. It has 7 pci 16 slots and 2 pci 1 slots. As soon as i install the 5th card cgminer stops working. I get cgminer has stopped and MM driver has stopped working.

I am sure that this issue has been brought up in the past but cant find a good thread on it. Any help would be great.

We need more info to help:

• What OS?
• What version of cgminer?
• Make sure to copy/paste any important error or log information as well
• What kind of coin are you mining?

A little bit of Google-fu turned up the following link.  Doesn't directly relate to bitcoin mining, you may find something useful in it.

http://www.xtremesystems.org/forums/showthread.php?285341-Load-Mmdriver-has-stopped-working-lt-error

I am running windows 7, Cgminer is 2.11.4, I am mining litecoin.

How do I get my error logs? I noticed that the machine has 2 copies of windows on it, I dont know if that could be related?

I may be wrong, but isn't Windows limited to 4 GPUs?  I want to say that used to be true, Windows could run at most 4, and linux could run at most 8.  It doesn't matter what the motherboard supports if the OS won't accept it.

Windows can handle 5 cards, thats not the issue.  The dual Windows isnt helping, but probably isnt hurting either. 

I would say its more than likely a heat thing.  Some card (or cards) are getting too hot being so close together and its shutting down.  What is your config for cgminer?

Oh, and probably wouldnt hurt to udpate cgminer.  2.11.4? Thats way old.  Many improvements made since then and are in the current version 3.3.1.

I will try updating cgminer.  I have a couple boards running 5 cards on windows 7. They are on risers with a large ac blowing directly on them. It cashes as soon as I install the 5 th card it never gets to mine. Wont even start with the 5 th card installed.  

If your other rigs are the same exact config, then its most likely either a board problem, or a card problem.

Updated cgminer to version 3.1.1 it was working then, I let windows update.. it had never been undated. Then tried adding the 5 th card again. It wouldnt load the drivers and now nothing works no matter how many cards are in the board. The CCC is now crashing I get CCC host application has stopped working and load MM driver not working and cgminer has stopped working. I have never got this board to fing work right. I think I am just gonna get rid of it. I think it is a really nice board. It is a p67 ftw, but if it wount run 5 cards I dont need or want it.

Did a system restore and got back to where I was 4 cards running and every time I add the 5 th  card it give load mm driver error.

What driver version are you running.

Have you tried physically swapping cards around on the mobo?  How about removing a card that you know works in a particular slot, and moving it to the slot where you are trying add the 5th card.  You'll still have 4 cards, but one will be in the new slot to prove/disprove that the slot is working properly.

Oh ya. I have moved the cards between all the different slots. if I put 4 cards on the pci 16 slots it gives the same problem. The only way I get 4 to work is 3 on the pci 16 slots and 1 on the pci 1 slot. If I put 2 cards on the pci 1 slots for a total of 5 cards I get the same error.

The slots are good the MB is good the gpus are good. There is not a hardware problem unless it is a limitation of the mother board.

? For the CCC ?

32bit or 64bit windows? It does matter...

This is the  board

http://www.google.com/imgres?imgurl=http://www.evga.com/articles/00604/images/P67FTW.jpg&imgrefurl=http://www.evga.com/articles/00604/&h=750&w=900&sz=209&tbnid=m8P78xQUYwUWIM:&tbnh=98&tbnw=118&zoom=1&usg=___C2NUPeO9xeZXnW2fo2Qut5DcSM=&docid=i6PIIMGS_7p8qM&sa=X&ei=jIP-UfS4H4LK9QSR44HQAw&ved=0CDEQ9QEwAA&dur=4433

I will check in a bit. I think that is the reason there is 2 copies of windows on it. I think I did 32 bit by mistake and then re installed the OS with 64

I think I might have figured it out. I think it is because I used the windows registration twice. I am going to load a new operating system and see if that was it.