Please help. New case and CPU MB will not POST. [motherboard ecs k7s5a] [amd athlon xp]

Q: I have a new motherboard (ECS K7S5A) and AMD Athlon 1800 + XP and I try to install a new case. Only when I mounted in the case of a video card, there is no display. The CPU fan starts and drives get power but no beep also.

Then I tried without the card still no beep codes. I think the MB is shorting, I do not know how to find out. I use all the space or stand offs that came with the case and that align with the holes in the MB. Then I removed MB from the case and I get the 3 beeps,