What exactly seems to be the issue right now? Seems like more of a software issue than hardware. BUT having different types of GPU brands could potentially be causing tribulations you've experienced. I have tons of mining websites saved when I did my research, I recall that using different GPUs together as Nvidia and RADEON was not efficient! Hope I can get more specific information from you with exactly what is wrong so we can get you mining and contributing to the network!

If you would, please try listing the issues; for example

1) computer cannot recognize all 6 GPUs
2) CG miner shuts down immediately after use
3) different drivers for different cards connected together?



Goodluck!