pxe boot

zen 7sp1 hp3
when hitting ctrl alt during pxe boot i get no maintenance mode.. it just flashes quickly and returns to pxe boot and exits out after finding nowork to do.. loaded hp3 in hopes of getting bootcd to work with new motherboard but the pxe boot maintenance mode will not work now with new or old motherboards.. is there somethingi'm missing.. i thought holding down ctrl alt was the way to get it to come up?