AZZA Solano 1000R CSAZ-1000R Full Tower Interior Paint Case (Black/Red) Pre-drilled holes located at bottom, allow efficient air flow when power supplyu is installed facing down. Bottom-mounted power supply:Power supply is bottom-mounted, can be installed facing either up or down. Optimized Cable Management: Cable is organized behind the pre-drilled motherboard tray. Allowing better cable routing and internal air flow. Easy Assembling: Thumb screw design for easy assembling of optical drive and HDD. USB & Audio ports located on top: USB & eSTA & Audio ports located on the top panel, allowing easy access.