I have an ASUS AMD HD 7770 and XFX one AMD HD 5450. I have one monitor hooked up to the 7770. And 2 smaller monitors connected to the 5450. I was wondering if there was a way to string the three of them together as one desktop. Main monitor is DELL 20" at 1680x1050 outer are DELL 15" at 1280x1024.