Show us your render settings please.

As with lights.
Start simpel, and build up to what your system can handle.

Try reducing bucket size.
Try IC at ZERO or 10 and build from there too.

Start by reducing bucket size. Might work out for you.
And YES; render in a serarate process.

For more, we would have to see the render settings.

Poser 1, 2, 3, 4, 5, 7, P8 and PPro2010, P9 and PP2012, P10 and PP2014 Game Dev
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