Have 4+ cards running on one of my rigs...took me months

[jwzguy]

First of all, here's my hardware setup for this machine:
MSI 890FXA GD70, 6core, 1000w OCZ
3x XFX 6870
1x MSI 6870

I finally got this running in windows 7 with 4 cards. Before you linux guys jump on me, I tried linuxcoin out, and I had 2 problems. I couldn't underclock 6870 memory, and when I went from 3 to 4 cards, linuxcoin wouldn't start Xwindows.

Windows wouldn't work for a while either. First, with 11.6 drivers, guiminer wouldn't start, Afterburner wouldn't start. I went to 11.7, which was nice, because it allowed remote booting, restarting the miners without monitors (dummy plugs have never worked for me), and the CPU bug was "fixed" - 1% CPU usage on 3 cards. But I could only start 3 at a time. GPUz wouldn't start if 3 cards were mining. 4th card also wouldn't start, no matter which 3 I started first.

I finally fixed this by uninstalling the drivers, deleting the contents of this reg key: 4D36E968-E325-11CE-BFC1-08002BE10318, and reinstalling 11.6. CPU back to 100%, back to monitor cable swapping, but it runs 4 cards.

I noticed overclocking is tricky. You have to switch between Trixx and Phoenix Rising to get the memory down, and use GPUz to check for success. Afterburner still wouldn't run. But GUIminer starts and runs now. Stable for an hour now. Power usage is 730W.

Been a long road...I hope this helps someone. Deleting that reg key was a breakthrough. Before that, going back to 11.6, win 7 wouldn't recognize all 4 cards. Driver sweeper doesn't delete that key.

[1715055957]

1715055957

[steamboat]

i'm running the same board w/ a dual core and quad reference 6950s . i had to delete that reg key as well to jump from 3-4, though i can run mine in quadfire without the need to use dummy plugs and my cpu load is only 50%. pulling 1.5 gh/s @ 800watts from the wall

[jwzguy]

i'm running the same board w/ a dual core and quad reference 6950s . i had to delete that reg key as well to jump from 3-4, though i can run mine in quadfire without the need to use dummy plugs and my cpu load is only 50%. pulling 1.5 gh/s @ 800watts from the wall

So the drivers are you using are 11.7? Do you mean 50% of one CPU or 50% over all?

On a 6 core machine, my usage is at 16%, because I have them set to use a single CPU @100%. But with 11.7 preview my overall usage was about 2%.

[steamboat]

im using 11.6, and 50% total cpu usage.

[burger]

something must be wrong with catalyst 11.7... now I have 16% - 17% cpu usuage on my 6 core amd phenom II. With catalyst 11.6 I had about 0% cpu usuage.

Now I have 11-7_vista_win7_32-64_xcode (the video converter) installed aswell, I don't remember if I did have it with catalyst 11.6.

[gnar1ta$]

Is it something with the GD70 motherboard, or the 6900 series cards??? I'm in the same situation.  Been trying for weeks to get 4+ cards running under linux with no luck, just get X running 100% CPU.  Maybe I'll give Windows a try.