ati6770

Hello, This is my actual computer: Processor: Intel i5 4570 Haswell 4th Gen Motherboard: Gigabyte H81M-D2V Rev. 01 Memory: 16 GB DDR3 Dual Graphic Card: ATI Radeon HD 6770 PCI-E x16 Hard Disk: 750GB SATA3 The problems are: The graphic Card doesn't work well with Yosemite 10.10, 10.10.1...