CHAN

Thanks for your information. I found the issue in Ironcad2016. The shadow result has a fault. I attached a picture to explain it. In Ironcad2016, you can get correct shadow after switch render mode to "shaded" and switch back to "shaded with edge". Or to click "Tools | Regenerate display". After that, the render result is same as one in Ironcad2017. Ok, now we compare the performance. Ironcad2017 is much faster. If the "Disable realistic" is checked, it will performance 3 times above faster in my machine. As your second question, now you can't do that. This fps display is mostly used for collecting debug information. And it will slightly slow the graphics performance as well.

We have tested many thousands of parts. IC2017 performance is much better. So 300 parts should be ok. That is better to let us have your files to address this problem. Would you like upload your files? Now i give you a few tips that may help you. Please check and try those options. Try the "disable some realistic effects automatically". If that works not well, to check "Hide small parts automatically". As a reminder, to set same lowest frame rate and max culling when you test the file in both ic2016 and ic2017.