When I wrote about using HD in Runscape I didn't give you all of the software and hardware being used.
I am Running Linux Mint - Elyssa KDE Community Edition. I let the system figure out what ATI driver to install and configure. Firefox 3.0.13 and java 6 Update 14 (1.6.0_14_b08). The hardware is a Dell inspiron 530 with an ATI Radeon HD 2600 XT card. The monitor is an Acer AL1717. I applied all of the patches to keep the system up-to-date. So far I have not had any problems with running Runescape in HD mode and I can swap between my desktops and resize the Runescape session without causing any problems or crashes.
The only thing we cannot do now is play various games that are Windows specific and I hope it is only a matter of time before the gaming companies figure out that Linux is a more-than-viable environment for their games. I prefer running Linux as we don't have to worry about trojans and viruses like when we are using windows. Even if there is an exploit the community comes up with fixes/patches much faster than proprietary operating systems.