Is it possible that a C++ program gives different results on different x86 hardware?
<p>i want to know if someone has experience with C++ programs which are built on a x86 system, and after releasing it for x86 systems (but for other processor hardware, f.e. AMD, Intel) some results differ. 
So the only thing that changed is the hardware.</p>

<p>The two things i have in mind are:</p>

<ol>
<li><p>floating point standard IEEE (I don't know how strict the processor manufacturers comply with that)
(Especially for iterative solvers, like FEM solvers, where one result is based on the result of the previous result. So small differences could lead to different results, f. e. 10000 iterations.)</p></li>
<li><p>Multi-threading </p></li>
</ol>

<p>I heard such things now several times.
And I'm just interested if there are some proofed facts related to that topic.</p>
