Is it something else thats making the screen go to the lines?? its like a bunch of vertical likes sometimes then other times its just a solid grey or white screen. is that the GPUs crashing?
I had that on my 5850's, you did something wrong when installing the drivers most likely (since the lines dissapeared for me after uninstalling drivers, might have been nvidia drivers fucking up, idk)
Anyways, how to most likely fix ur shit:
1. Download Driver Sweeper ( http://www.phyxion.net/item/driver-sweeper.html
2. Boot into safe mode, run Driver sweeper. Proceed to remove all your graphic drivers.
3. Uninstall any overclocking tool that you have used.
4. Reboot into windows and install new drivers, i installed the previous version of drivers for my cards, but i don't really think it should matter.
Try to avoid the 400-600mhz mem clock if it causes problems for you (doesn't for me, but i'm never @ 500mhz for any longer than 20s with nothing running in the background), go from 700->300.