VirtualBox 5.1.0 版本發布，這是一個重要的更新，主要是在性能的提高和多媒體的支持上。
更新日誌：
VMM: new APIC and I/O APIC implementations that result in significantly improved performance in certain situations (for example with networking, bug #15295)
VMM: added support for Hyper-V paravirtualized debugging of Windows guests
VMM: emulate even more MMIO and shadow pagetable exits without going back to user mode
GUI: overall migration to Qt5 (bug #11775)
GUI: passive API event listener improving the VM GUI performance and response time
Audio: added HDA (High Definition Audio) support for newer Linux guests
Audio: added on-demand timers which should improve the overall performance and reduce the CPU consumption
Audio: more fine-grained volume control for the AC'97 emulation, which now also takes the master volume control into account
better support for Python 3
添加/修復了以下項目：
VMM: activate the x2APIC by default for Linux guests
VMM: many more fixes
GUI: the Detach UI action is now a part of the VM Machine menu
GUI: reworked session information window
GUI: the new VM wizard now allows to choose the VM location for the VM which is being created
GUI: fixed location of touch events in unscaled HiDPI mode (bugs #14366, #14367)
GUI: various bugfixes and internal cleanup
Storage: use fallocate() or similar if present to speed up creating fixed-sized disk images (bug #5967)
Storage: implemented NVMHCI-compatible storage controller
Audio: various bugfixes and infrastructure improvements
E1000: implemented interrupt throttling for performance improvements
EFI: many improvements, for example allow to boot from USB
OVF: improved handling of signed manifests
API: Windows XP guests and Windows 2003 server guests now default to the E1000 T Server network card
VBoxSVC: fixed several memory leaks when handling .dmg images
Installers: ship VBoxBugReport
Windows hosts: reworked COM proxy (e.g. bug #8298)
Linux installers: no longer rely on DKMS for module rebuilding
Linux Additions: fix a problem when updating the initramfs after the guest modules are compiled (bug #15579)
Linux Additions: try to fix a problem where the OpenGL libraries where loaded by the X server when we only support X clients (bug #15574)
詳情：https://www.virtualbox.org/wiki/Changelog