I am running a mac pro on osx yosemite dual core xenon with radeon hd5770 graphics and it wont render in gpu compute. says it has a problem with render kernels
Sort Answer: Your card is not suported
OpenCL GPU compute for AMD GPUs is not on the same level of support as Nvidia, there are lots of known issues, limitations, and unsupported features.
Edit: As of Blender 2.79 some serious improvements have been made, supported by AMD themselves, OpenCL GPU computing is now more viable and practically at the same feature level as CUDA based solution. Still, as of 2.79a, be aware that there are rough edges, bugs, and overall it is not as polished as NVidia hardware.
Besides that, GPU computing on OSX is not as performant as on other platforms. If you are serious about GPU acceleration consider other platforms like Linux or Windows.
Basically AMD HD 5### seris is no longer supported for Cycles rendering, as stated in the Blender Wiki