Is it possible to run Windows XP from a RAM disk?

"Yes, it is possible.

To run winxp in ram (full winxp or mini is up to you) you need to make a vhd disk image which includes the winxp that you want. The winxp has been installed with winvblock driver.

You can use oracle virtualbox to creat the need vhd disk image.

After all, you will need grub4dos to load and boot the image

Summary command : grub4dos# map --mem /winxp.vhd (hd0) ...

See more detail steps and screenshot here : http://www.linuxbyexamples.net/2012/08/how-to-run-winxp-in-ram-memory.html

Hope it can help you.

Cheers."

"I guess you could build something out of the following components:

CPU with hardware virtualization support
some trimmed down linux kernel with ramdisk
a virtualization software which supports hardware virtualization (KVM, Virtualbox i.e.)

Here is what it would do:

PC boots linux
kernel unpacks ramdisk and creates an large enough ramdisk
virtual disk is copid to ramdisk
software virt. boots XP in VM and switches to fullscreen

This would be a pure software solution without the need to ""hack"" Windows. But you would have some small overhead due to virtualization."