CGMiner help needed

[draugauth]

Ok first off the build

MSI Z77A-G45 Motherboard (7 PCI-E slots but only 6 usable ones as 2 are married)
6 Sapphire HD 7950's
Intel I-3 CPU
4GB ram
Corsair AX1200i PSU
PCI-E powered risers (3 16x to 16x and 3 1x to 16x)

cgminer-3.1.0-x86-64-built
xubuntu 12.10

When I use the --thread-concurrency 20000 (or higher) cgminer disables 5 of the GPUs.   If I don't use thread-concurrency at all it disables 5 of the GPUs.  If I use a thread-concurrency under 10000 then all 6 video cards mine but at less than 1 card does by itself.

Any suggestions?  I'm about to download and try some older versions of cgminer incase this is a bug with the newest build.

Thanks in advance.

[BitshireHashaway]

The first thing I would do is try some of the older versions of cgminer to see if its a bug. If the older versions work why upgrade? However, I would recommend the source of your problems as you putting in the incorrect thread concurrency. Try researching and putting in the actual thread concurrency of your graphics cards rather than trying random numbers.

[theskillzdatklls]

make sure to keep some duracell batteries on hand to continue mining in case your power goes out due to a thunderstorm or worse yet an earthquake.