See below the information from the consol. My GPU seems to be stuggling. I've had a couple of iffy renders with the GPU in Cycles as well. The buckets haven't all remndered the same leaving the final render like a jigsaw, with some of the buckets having rendered slightly different and therefore leaving that bucket standing out like a sore thumb. Also the GPU doesn't seem to be rendering any faster than the CPU. I have a Gulftown 980X Extreme edition and 16GB Ram. Not sure if it's a bug I'm encountering i think it might just be my GPU not up to the task. But I thought if anything it would just render slower rather than mess up. Some confirmation would be cool.

Thanks
John

Read prefs: C:\Users\User\AppData\Roaming\Blender Foundation\Blender\2.80\config\userpref.blend
AL lib: (EE) UpdateDeviceParams: Failed to set 48000hz, got 44100hz instead
found bundled python: C:\Program Files\BlenderOctane\2.80\python
OctaneBlender Engine Init
Read blend: D:\Blender\41-blender\blender\Monkey.blend
OctaneBlender Engine Create

Octane: ERROR. Server log:

Failed devices:
GeForce GTX 680(device 0), error message: "CUDA error 2 on device 0: out of memory -> failed to allocate device memory"

Last Octane engine log entries:
CUDA error 2 on device 0: out of memory

-> failed to allocate device memory

device 0: failed to allocate tone-map buffers
device 0: invalid memory pointers passed

OctaneBlender Engine Free
OctaneBlender Engine Create

Octane: ERROR. Server log:

Failed devices:
GeForce GTX 680(device 0), error message: "CUDA error 700 on device 0: an illegal memory access was encountered -> failed to create link"

Last Octane engine log entries:
CUDA error 700 on device 0: an illegal memory access was encountered

-> failed to create link

device 0: failed to create OSL compile context:

device 0: failed to compile module 0