... like things fitting inside the existing case...

- happened to me once with a build, when the hard drive cage was too close to the cooler for the chipset, and the RAM slots sat behind the power supply. Talk about "tweaking" things... I was close to taking a hammer to it...

- my previous motherboard had been 1 1/4" shorter, and was an "odd" size, compared to most others.
Good luck with the build RR. I love doing that. Do you have plans for your old video card? cpu? ram? I might be tempted to take them off of your hands for a small fee... me paying you, of course...

- unless you think it might have been a power surge that took out your mother board??