2832 x 2128 230 DPI They're taken with an older 6.1 mega pixel camera, I like to work with the largest photos I can, then reduce the file size so I can email them. Version 3.5.11 works fine, and I use photos of this size all the time. Not even Photo Shop eats this much CPU usage _ it starts to use RAM saving things in history when using the cloning stamp for example, but even when using an application, the rending of the photo doesn't suck up all the CPU usage. It doesn't matter, I'll stick with 3.5.11, I just thought I would let you know.
This beta only works smoothly on my gaming machine with it's Haswell i7 Processor to which it's almost maxing it out at 80% CPU usage (3.85 Ghz.) in the task manager. With all the other machines in my house which are simple dual cores running at around 2 Ghz or more, the ellipse tool is jerky and broken. There is even an older machine at work, still with in the specs _ when I type into a photo, I can type faster then it appears in Paint.net. _ it's very jerky. These are large photos of 1 and 2 MB, but the non Beta ones works OK, but not this Beta. It's using all the CPU and no RAM. Ticking or un-ticking the GPU acceleration button makes no difference.