Ubuntu under VirtualBox 4.3.12 r93733 run slow on Windows7 with AVG free 2011 Ubuntu VM **speed is subjectively 5 to 10 times slow**. Tried setting CPU number, PIIX3/ICH9, Display 3D acceleration. Still slow. Any pointers appreciated. VirtualBox installed with all default setting. Ubuntu 14.04 Desktop installed as the only VM. In separate test, Ubuntu run fine as USB Stick LIVE (without install to hard disk) Intel i5, 2.8GHz, 4 cores, 4G RAM, Windows 7 At first, installed latest VirtualBox 4.3.14. Run error. Web postings refers to bug ticket stating that it conflicts with several anti virus software and recommend use 4.3.12 and I did that. It **runs slow. Tested a few functions, seem ok**.

There has been problem with 3D acceleration for 4.3.10 and 4.3.12 with Ubuntu guest. It is advised to find earlier version further down the road until getting one that works fine.