Apple has released a firmware update that addresses a handful of issues on early 2009 Mac Pros. The update improves "compatibility with virtualization products utilizing VT-d, storage performance under Windows XP for Boot Camp users, and system reliability during the boot process." To install the update, follow the instructions in the updater application that launches automatically after the installer has closed (/Application/Utilities/MacPro EFI Firmware Update.app). More information regarding installing a firmware update on an Intel-based Mac is available on Apple's Web site. The update is available via Software Update and the Apple Support Downloads page. (Free, 1.96 MB)
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