Windows 10, Nividea 630M.
Broken: 2.76 dde4fc6
I now think this never worked.
Short description of error
Using the demo Barcelona blend file.
Set my render engine to GPU
And then turning on render preview in edit mode, then Blender Crashes with a TDR has been detected.
Meaning an Error that the GPU timeouts on responding back to the system.
Strangely though .. rendering the scene F12 (that's not the preview mode), works fine.
Also if i Enable progressive render mode to do a final render it works fine too.
I thought not all effects are in preview mode, so it should render render more lightweight, but apparently its not.
I'm suggesting maybe its an idea to have preview mode work in tile chunks too, or in a progressive like mode.
I think the crashing happens not upon uploading the model to the GPU, from the looks of it, 1 preview cycle is rendered (but even with setting preview to 1) it still crashes.
Exact steps for others to reproduce the error
Simple barcelona-paviloen demo scene, and a low end graphics card,
(1) i first thought this never happened in older versions, but i was wrong, my own project simply got bigger
(2) This is not something critical to me, i dont depend on it, workaround is to use CPU i7 for larger blend files.
(who with latest updates seams to speed beat gpu again)
(they're speed is about roughly the same, depends on build).