Is it possible to render a heightfield with 1 triangle strip? if so, what''s the algo to do that?

Actualy you can but it''s a bad idea. Split your terrain into chunks(16x16 or 32x32) and first do some frustum cullling and then only render posibly visible chunks of terrain. Also try using VA/VAR/VAO first...

There are more worlds than the one that you hold in your hand...

I''m not talking about a terrain. I use a CLOD algorithm for my Terrain and it works fine... this is for something else... so would you be so kind please?

I don''t think, especially with CLOD, that you can do this... the triangles all have to be connecting, so this would be trouble with CLOD... maybe with a static heightfield, but this would probably cause more trouble than save time.