Hello,

I bought a MSI Z77A-G45 Thunderbolt motherboard and currently 2 600W power supplies. I wanted to mine with 4 cards for the beginning. A 7950, 5870 and 2 5850. May add two more cards later and buy a third power supply.
I wanted to rise 3 of the GPUs with x16 to x16 risers unpowered and 1 or later 3 with 1x to 16x which I will modify to be powered.

Will this setup work power wise and everything or will I get some problems with something and do I have to change/modify something?

And are the GPUs ok with getting power from those things?

2x sATA --> 6Pin-PCIe


I am really thankfull for every little help.
Greetings