Mac Pro EFI Firmware Update 2.0 was released by Apple Thursday afternoon, and is recommended for all new cylindrical Mac Pro models. The update reportedly improves system reliability during the rebooting process.
Apple also said the update will resolve an issue related to memory self-test with the new desktop. And the new firmware will also improve graphics power management when using Boot Camp to run alternative operating systems to Apple's own OS X.
The 5-megabyte download is intended only for the new Mac Pro, and requires OS X 10.9 Mavericks or later.
Preorders for the Mac Pro began earlier Thursday, with the first shipments scheduled to arrive by Dec. 30. However, Apple appears to have sold out of much of its initial supply, as orders of standard configurations are now not advertised to ship until February, and some custom orders will take even longer than that.