Render difference

TIP: You need to add more background data like:
- Operating systems (make, version)
- Blender Version
- Used Render engine (Blender Internal, Cycles, other)
- Render settings
- Camera settings
- Actual screenshots from your render-errors
Without this information it is very hard for others people - who want to help you - - to find out what is going wrong on your computer.

Do you mean like when you set off a render, the image starts rendering from the middle out and sometimes it renders from like, top to bottom?

It might have something to do with your render settings.  So, under Render Settings (the camera), there will be a Performance menu.  Under Performance, there will be a section called Tiles.  Under that there's a drop down for how you want the image to render the sections of the image, such as Hilbert Spiral, Bottom to Top, Right to Left, etc.  I think it's just more preference to how you want to render something, or if there's something you want to see rendered right away, say, in the middle section, then Hilbert Spiral will start there and render out in a circular way.  This way, you can check a critical area to tweak and make sure it's alright without having to render the whole thing.  The size of you image could be affecting how it renders, as well.  If you've got a 256x256 px image, and the tile size is set to 16x16 with a Hilbert Spiral, then it'll render out smaller chunks and look like it's in a spiral.  If it's a 256x256 image and the tile size is 128x128 with a Hilbert Spiral, then it'll look like a box because it's rendering a much bigger chunk of the image at once.

Without much info to go on, this is my best guess.  Flesh out your questions as best as you can next time.  We're not telepathic, so as much info as you can give, especially for something technical, the better we can help you.

thanks...figured in render section, just not seeing it.....will take closer look