I have a Gigabyte GA-Z68X-UD7-B3 motherboard. In an SLI configuration with one Nvidia GTX-570 card in the 16_1 slot and the second in the 8_2 slot, I get occasional black screens or graphic abnormalities. With the two cards in the 16_1 and 16_2 slots things (so far) seem to be okay.
When using just one card and it is in the 16_1 slot then there are no problems but But if the single card is in the 8_2 slot, then I get black screens.
Is this a problem with the motherboard is there another logical explanation?
Do you have the SLI ribbon strip connector connected between both cards? Also is your power supply up to the task of 2 x 570s ie. is it a good brand with enough watts?
Yes, the two cards are connected with the ribbon; the ribbon is removed for the single-card setup. The power supply is a 1000 Watt Silverstone Strider Gold ST-1000G. I think this is a very good power supply. Also, the cpu is an Intel I7-2600K.