Help Please for Crashing Gigabyte 7950's

[odie158]

Hi All
I would really love some help solving a problem I am having with my rig. I just installed my second GPU (Gigabyte 7950). Each GPU will mine fine by itself but when I try to start them both my system immediately crashes. I have been using bitminter because of it's ease of use but trying with guiminer I had the same results. I have never been able to figure out cgminer(?). any help at all would be appreciated.
MOBO: MSI 970a g46
GPU's: Gigabyte WF3 Rev2 X2
AMD Sempron 145
PSU: 850W
I am at a real loss here. Should I try the crossfire cables?
Thank You

[af_newbie]

Hi All
I would really love some help solving a problem I am having with my rig. I just installed my second GPU (Gigabyte 7950). Each GPU will mine fine by itself but when I try to start them both my system immediately crashes. I have been using bitminter because of it's ease of use but trying with guiminer I had the same results. I have never been able to figure out cgminer(?). any help at all would be appreciated.
MOBO: MSI 970a g46
GPU's: Gigabyte WF3 Rev2 X2
AMD Sempron 145
PSU: 850W
I am at a real loss here. Should I try the crossfire cables?
Thank You

Throw away those crossfires, guiminer and bitminter. 

Learn to use cgminer or bfgminer.  Setup both cards with default clocks. Download GPU-Z to view the RT clocks.

Once you have them both running with the default clocks, increase core on both until you get h/w errors.  Back down with core a bit, start lowering memory until you get significant drop in hash rate.

Download MSI afterburner to set clocks to whatever you want.

[mccminer]

Have you tried dummy plugs?

[jhk753]

You should also have a look at this thread: https://bitcointalk.org/index.php?topic=165490.0
I don't know what OS you use but it might be helpful

[odie158]

Hi All
I would really love some help solving a problem I am having with my rig. I just installed my second GPU (Gigabyte 7950). Each GPU will mine fine by itself but when I try to start them both my system immediately crashes. I have been using bitminter because of it's ease of use but trying with guiminer I had the same results. I have never been able to figure out cgminer(?). any help at all would be appreciated.
MOBO: MSI 970a g46
GPU's: Gigabyte WF3 Rev2 X2
AMD Sempron 145
PSU: 850W
I am at a real loss here. Should I try the crossfire cables?
Thank You

Throw away those crossfires, guiminer and bitminter. 

Learn to use cgminer or bfgminer.  Setup both cards with default clocks. Download GPU-Z to view the RT clocks.

Once you have them both running with the default clocks, increase core on both until you get h/w errors.  Back down with core a bit, start lowering memory until you get significant drop in hash rate.

Download MSI afterburner to set clocks to whatever you want.

I am downloading afterburner right now. That's what I thought about the crossfire cables. And I will keep trying in cgminer. Thank You. Any additional input is always appreciated.

[odie158]

Maybe I am getting some ware with cgminer because it crashed immediately too. I do not think it's a dummy plug issue because it crashes so fast (not even one second). I must do a hard restart to get my computer running again.

[mccminer]

What OS are you using?

[odie158]

What OS are you using?

Sorry didn't answer before Windows 7

[cloudstrife07]

try disabling PCI-e Gen 3 in the BIOS. 

[odie158]

  Ok, I've figured out how to use cgminer. Made a dummy plug. I only have PCI-e 2.0. Downloaded MSI afterburner. It still won't work with two GPU's though each will work by themselves. This is my next guess: I only have one DIMM of memory (2GB) I am wondering if each GPU needs it's own channel and I need another stick. Does anyone have an opinion on this?

[HellDiverUK]

Dummy plugs aren't needed.  I don't know why people keep on rhyming on about them.  

YOU DON'T NEED DUMMY PLUGS.

*cough*  Now I've got that out - which version of drivers are you using?  I tend to stick to 12.10 drivers - I've had some weird stuff happen with the 13.x drivers.  I'm running a Gigabyte 7950, an Asus 7850 and a Sapphire 6970 all in the same machine, running Win7x64 with 12.10 drivers.  

With the 13.x drivers I had the same problem, CGMINER just crapped out immediately on run "CGMINER.EXE has stopped working".  With 13.x all I could get to run was Reaper for LTC mining.  cgminer wouldn't run at all...

2GB RAM should be plenty.  I'd try cleaning out all the drivers, and try a minimal install of 12.10 - just the driver and the SDK runtime - nothing else.

[odie158]

Hi all. I think that I figured out the problem. I cheaped out on the power supply. I had a $50 Kentek 850w power supply and once I finally got both cards running it ran for about 2 minutes then blew up (flash, smoke and everything). I sent the mobo, PSU, power supply, and one of the GPU's back to amazon (great return policy) and got a $120 cooler master 80plus gold certified PSU instead. it is running great with the single card and I have no doubt that it will continue to run well once I gat another card too. the moral of the story is: Don't buy a cheap PSU and Amazon has a great return policy. Thank you to everyone for there help!!!