here are my times to render
cpu is better for my head. my grafix card makes some loud noices when heavy calculating. ( loud cooler fan i think )
Looking on the screen I was quite surprised like whhhhaaaat? my GTX660 makes it in 3 minutes, how are you getting 4+ with GTX 770? And then after some tests I noticed that It is default values xD
Besides, there is something quite strange about your values.
Michael gets 6 minutes result with his i7 3.8 Ghz which is pretty powerful processor, what kind of CPU you can possibly have to get it in 4 minutes?? That kind of CPU is usually comes with some powerful GPU that should be capable of making it in 1-2 minutes.
And your values are quite similar, what CPU and GPU do you have? You must be running those test on a laptop, right?
CPU: i7-6700K @ 4GHz
GPU: Nvidia 1070 with 8GB GDDR5, 1582 MHz
Best CPU render time (64x64 tiles) 2:49.27
Best GPU render time (480x270 tiles) 1:02.25
I tried square multiples of 2 for the tiles, but it seems to like it best when the full frame is even multiples of the tile size; in particular when it’s 1/2 of the full frame. I wonder if this is a function of overhead required to render each frame?