So, here is the situation …

I am looking around in center of a textured cube.

Using …

glRotatef(aX,1,0,0)

glRotatef(aY,0,1,0)

If aY is near of n*180 i get ~23 FPS
and if aY is near of n*180+90 i get ~93 FPS.

What is causing this?

Other info :

a) Evry side has the same mipmap texture.

b) If i disable texturing i get ~140 FPS at evry aY (and aX) value.

c) I have lighting enabled with one light at eye point