Ultra Products introduced the MicroFly (small form factor) case just a short time ago and not too long after that a small design flaw was found. If you are using a 6 inch deep power supply, the X2 and 600W offered by Ultra, two small tabs are in the way. These issues have been correct by Ultra Products, unfortunately a few cases did get shipped out. The fix for this is super easy and takes very little time to complete and I will show you how I corrected this issue.
If you have one of these problematic cases, check out the informative how-to at Modders-Inc.