Blender2.75a
Don't' you use normals to make a mesh look smooth like they look when there SubDed even if it's not SubDed ?
How do you get a normal to make a mesh look smooth like they look when there SubDed even if it's not SubDed ?

1.Not SubDed No Normal

2.SubDed No Normal

3.Not SubDed with Normal

4.SubDed with Normal

How do you make a low polycount game mesh ,look smooth ?

 & where in Blender is the meshes polycount at ?

1. You need to Bake the Normals of the high resolution model, and apply the normal map result to the low poly object.  The baked normal map will change the appearance of the low poly model, to approximate the smoothing and details of the high poly version at a distance.

2. You can see the statistics of any selected object at the top of the screen, next to the render engine drop down box.  In object mode, you will get the overall statistics, and in edit mode, you get the stats of the selected object.  There are other ways to retrieve this information as well, but that's the basic, fast way to ascertain certain details.

Here's a screencap showing where to find the scene statistics.  In object mode, it will give you the overall stats, and if you select an object, and enter edit mode, you'll get more object-specific statistics.

Thanks a lot for your help. 

My bad ,I should have said how I made the maps.

I modeled the mesh in another app polycount 1400. then I exported to zBrush.razed the polycount to 5.734 million.
I made the normal map and a displacement map in zBrush.

Then in Blender .I loaded mesh polycount 1400 added the normal map using .jpg in the texture thing on the right. 
then in mapping clicked the normal box .

So there is not 2 different meshes. 

RorrKonn, are you rendering with BI or Cycles?  Make sure the normal map you baked is a high resolution, or some details will be lost.  Here's a tutorial by Sardi Pax on how to create and use normal maps in Blender.  Maybe this will help.

https://www.youtube.com/watch?v=OKXg5oHDz_4

I clicked the camera icon in the thing on the right that has all the icons camera ,material ,texture etc etc .
and then I clicked render. So what ever it's set on BI or Cycles is what is was rendered in.
I know very little about rendering in any app and very little about Blender .

I watch ya youtube video ,I'll half to study it better.

Wouldn't saving a normal map out of zBrush with a 5 million polycount be the same as burning a 5 million polycount mesh in Blender ? 

How do you move the camera in camera view and get it to stay in camera view ?
I thought I booked marked that video but can't seem to find it now.

Wouldn't saving a normal map out of zBrush with a 5 million polycount be the same as burning a 5 million polycount mesh in Blender ? 

Not always.  It can depend on how the Normal maps were generated in tangent space..  OpenGL engines will display the generated relief differently than DirectX for example, and different software may handle the maps differently.  If that first tutorial doesn't help, try this next one.  It shows a direct pipeline for creating Normal maps in Zbrush for Blender. https://www.youtube.com/watch?v=OjqbshrDjXM