Using Virtualbox 4.3.14 on a Compaq C700 with 2 GB of RAM, no VT-x. For legacy Windows stuff I use a Windows 2000 guess, and it performs better than native Win2k on similar hardware. (Probably scalability issues with Win2k, but still.) 30 second boot time, runs without any lag. Tried some Linux guests though, and they are astonishingly slow. 5+ minute boot times, crazy cursor lag, 99% CPU usage on both cores on the host. This is the case even with guest additions installed. I/O to the virtual hard drive is particularly slow, by looks less than 1/8 the speed on the host. Has anyone seen this? Any ideas? I know VT-x would help a lot, but it is not an option with this laptop, and right now (AFAIK) Virtualbox is the only open source player in town.