This makes sense.. The info was probably in this thread, but 700+ pages

So if I plan to get any newer cards, I can't really mix either. Maybe I should offload these 950's and get something newer... Sounds like it will be much simpler lol.
Still having problems even in Windows. When I put in a 7950 and a 280x (Almost the same, both Tahiti etc), then the 280x always goes straight to full fan speed, but it's fine when it's in on its own.
I just did some card shuffling so I now have 2 Sapphire 7950's in the same box and the 280x is in my son's machine... Let's see.
I'm gathering I may be better off sticking to Windows then while I have these older cards...