Mich, you might want to try powerlogix's arcrylic case, designed to offer better air circulation for the faster cubes. It can be found here http://www.powerlogix.com/products/enclosure/index.html.
"Fix it 'til it Breaks."

Jacob - EiC & Director of Technology
Mac Pro Quad 2.66 - 4GB RAM
160 GB SATA RAID 1 - 650 GB Storage
Quad 19" Widescreen LCDs
Accessorized to the Hilt