I just installed the 4.0 beta, and its working great except for GPU rendering. It'll flicker any time I move the cursor across the canvas. Here is a video showing the issue. The diag info shows two 660Ms, but I only have one 660M and an Intel HD4000
Diagnostic info:
Application paint.net 4.0 (β 4.0.5168.12074)
Build Date Monday, February 24, 2014
Expiration Date Monday, May 19, 2014
Hardware accelerated rendering (GPU) False
Animations True
Language en-US
OS Windows 8.1 (6.3.9600.0)
.NET Runtime 4.0.30319.34014
Physical Memory 8,091 MB
CPU Intel(R) Core(TM) i7-3610QM CPU @ 2.30GHz
Architecture x64 (64-bit)
Process Mode 64-bit
Speed ~2295 MHz
Cores / Threads 8
Features DEP, SSE, SSE2, SSE3, SSSE3, SSE4_1, SSE4_2, XSAVE
Video Card NVIDIA GeForce GTX 660M
Dedicated Video RAM 1,985 MB
Dedicated System RAM 0 MB
Shared System RAM 2,048 MB
Vendor ID 0x10DE
Device ID 0x0FD4
Subsystem ID 0x397717AA
Revision 161
LUID 0x000A997C
Flags None
Video Card NVIDIA GeForce GTX 660M
Dedicated Video RAM 1,985 MB
Dedicated System RAM 0 MB
Shared System RAM 2,048 MB
Vendor ID 0x10DE
Device ID 0x0FD4
Subsystem ID 0x397717AA
Revision 161
LUID 0x000CD3C6
Flags None
Video Card Microsoft Basic Render Driver
Dedicated Video RAM 1,985 MB
Dedicated System RAM 0 MB
Shared System RAM 2,048 MB
Vendor ID 0x1414
Device ID 0x008C
Subsystem ID 0x00000000
Revision 0
LUID 0x000CD301
Flags Software
EDIT: Setting PDN to use the integrated Intel HD4000 makes the flickering stop. It would be nice if I could use the 660M though, as GPU editing is a bit slow with the HD4000.