Program freezes for minutes after rendering

[narmer]

When rendering large images (for example 8000x4500 px), after the rendering process is finished, 3ds max freezes for minutes (it occurs, when the render dialog is still open, it says "rendering done", but the program is frozen for about 15 minutes). I have 16 GB RAM, and i7 processor.
Saving the images also takes a lot of time, especially when I'm saving multiple render elements.

Is this normal? I'm guessing it might be the lack of RAM, but I'm not sure. What might cause the problem?

Thanks,
Gabor

[Morbid Angel]

If your ram is at the max during rendering, it could be related. Are you saving to .vrimg? if not this could help.

[Vizioen]

I have the same problem with a 24 and 64 gb ram machine. But my scenes are almost never optimized, there's never time for that. The way I see you guys talking about mipmap and LOD trees and texture sizes and saving to vrimg and whatnut, could probably be helping me but it takes a bit time and research to figure this out and it takes time to set it up too. Plus I wouldn't know what would need optimizing. Maybe a thread with all the helpful tools and tricks/tips to optimize a scene could be made.