Looks like you have mold or corrosion in that case, I'd spend $30 and get a new case, make sure you are not using it in a humid environment or storing it in a damp basement. Why are you just upgrading only the motherboard? That will do almost nothing to make the system faster and often not better, aside from maybe allowing better overclocking or RAM speed or just adding some more ports. Really things that you may not even need.