Generated mesh not showing up on my laptop

Hey, I've run into a weird problem. I have a mesh generation code which works nice on my desktop computer, but it doesn't work on my laptop. The mesh is generated, but it won't show up in the scene or the player view. The mesh filter does indeed say "Instance", and the Stats window says the correct amount of triangles (which changes if I enable / disable the game objects, as one would expect). I've also checked that the object's not on wrong layer and all the layers are visible. I've tried both recalculating normals and bounds, and it doesn't do anything. It can't be a problem in the materials, textures or UVs because the mesh won't appear in the wireframe mode in the scene view.

Both computers are less than a year old, and both have the latest graphics drivers. The only thing I can come up with is that my desktop has nVidia's graphics card, while the laptop has Ati's.

So... Is this a bug in Unity3D, or am I missing something here?

EDIT: So, I just tested with a really simple script like this:

     Mesh mesh = new Mesh();
     Vector3[] verts = new Vector3[3];
     verts[0] = Vector3.zero;
     verts[1] = Vector3.up;
     verts[2] = Vector3.right;
     
     int[] tris = new int[3];
     tris[0] = 0;
     tris[1] = 1;
     tris[2] = 2;
     
     mesh.vertices = verts;
     mesh.triangles = tris;
     
     this.gameObject.GetComponent<MeshFilter>().mesh = mesh;

This seems to work on both computers. But, the problem code that produces the problem is a lot more complicated, creating objects with about 10k vertices. The vertex limit is at 65k I think, so that shouldn't be the problem. Is it that ATI's graphics cards cannot handle certain meshes or..?