Heh, today finally I got the chance to install Ubuntu 64bit on an AMD Turion 64bit laptop.
The laptop runs nicely with Ubuntu, with all drivers detected save wifi (Broadcom chipset) which requires ndiswrapper, however the latest Linux kernel at this writing 2.6.17 seems to support broadcom without the need of windows binary driver.
So if you're looking for a nice laptop that play nicely with GNU/Linux, then I suggest that you look into Compaq Presario laptop series (the one I'm testing now is v2613 priced at RM2,499).
Please refer to [tuxmobil.org] For more information on other users experience on using Compaq laptop with linux operating system