I have been working on a scene of an apartment within Poser and am having trouble rendering my final pictures.  I think that the problem may be that my scene just has too much stuff in it and the renderer just cannot handle the rendering process.
I have tried removing anything that will not appear in the current camera view, but it made no
difference.

The problem that I am getting is that after a long time of rendering, the final result turns out to be just a quarter of the whole picture (half in some cases).

I have tried everything I could think of and am basically giving up on my project altogether.  HOWEVER, because I have spent almost 3 months working on this thing, I want to be sure that there really IS nothing else I can do before I officially throw in the towel.

Im not very good with configuring the Poser settings, so I was thinking that maybe... just maybe... I have something tweaked funny that is causing problems.  Im posting my configurations here, so maybe someone can tell me if I messed something up.

Here I go:

COMPUTER:
-Motherboard: ASUS P5LP-LE (Leonite)
-Video Card: NVidia GeForce GTS250, 1GB (Driver 190.62; I gave up updating because the updates made many of my computer games stop working)
-Processor: Pentium D 960 3.6GHz
-RAM: 4GB
-OS: Windows 7 32bit Home Premium; up to date with all Windows updates.

POSER:
-Version: Poser Pro 2010 8.03.11916
-Under General Preferences, 2 Threads are selected for rendering, as well as the "Seperate Processes" checkbox
-Dimensions are set to 1280x720 @ 300 Pixels/Inch
-Cast Shadows is checked
-Raytracing is checked (I NEED raytracing for my scenes).  4 Bounces, 90 Irradiance Caching.
-Indirect Light is UNchecked
-6 Pixel Samples

• 0.50 Min Shading Rate
  -Max Bucket size is set to 5000 (also tried 15000... I REALLY dont know what to put this as, but 15000 and 5000 work fine for very low quality test renders)

Any other details can be provided.

Im basically trying to get the best quality possible and I am not ready to upgrade my PC yet (it would cost too much).
Any help would b appreciated and I can rephrase anything I just typed and/or provide any additional details.