Why do I have "Out of memory" crash while GPU rendering with the memory peak of 356 when by graphic card has 2GB of memory?
As first I must say only for correctness: Does not matter, how much memory have you graphics card. Important is how much free memory have your graphics card, when you start render. Keep in mind: system need some video memory for running.
You are not only one who have this problem. I thing Blender have some issues with freeing VRAM. I used Win and now I'm using Linux and it's the same. What help is restart Blender.
About peak of used VRAM - I don't thing this is correct number in case of error. From my experiences, if Blender give you "out of memory" error, this number is incorrect. You can determine exact size of scene by switch to CPU rendering and you can see how much memory is really used for your scene.
best way for work with render and GPU is to use integrated GPU (o a very cheap video card) for the system and use the powerful GPU just for rendering. in this way GPU is just used for rendering and nothing else.
if your computer have a integrated VGA try to plug monitor in this one and let the 2GB card unplugged.
try to start rendering in this way