I had to find out why Google Earth was so slow on my Ubuntu machine. Every other application works flawlessly (or nearly so) except Google Earth. I should have figure it out and not blamed Ubuntu, but I have a bad habit of 'ready, shoot, aim'. And it got me again this time.
When I came home I booted up Ubuntu, made a safe copy of xorg.conf, and then fired up the Restricted Drivers applet (System | Administration | Restricted Drivers Manager):
There's only one entry, for the ATI accelerated graphics driver. After clicking the Enable button, Ubuntu, through the synaptic tools, installs the drivers and configures the system to use them. You're then asked to reboot the system to finish enabling the drivers.
When the system came back up it was in 1024 x 768 and 60Hz refresh. There was no higher resolution. I knew then it was coming out, since the non-ATI drivers produce a reasonable 1600 x 1200 resolution. But while it was in that mode I fired up Google Earth, and found it was every bit as responsive as the installation on the big Athlon 64 based system at work. I zoomed, I panned, I flew all around the globe with nary a dropped frame or hesitation. So I zeroed in on New Orleans, turned on 3D Buildings, and captured an elevated perspective.
Ubuntu 7.04 had nothing to do with Google Earth's initial poor performance. Instead it had to do with the selection of video drivers. I have an nVidia FX 450 video card on the Athlon 64 system and it's using the nVidia 64-bit drivers under SLED 10. A key to Google Earth's good visual performance is hardware acceleration provided by the vendor's proprietary video drivers.
Right now the Ubuntu system is back under the Xorg Radeon driver so I can enjoy the greater screen resolution. Later this week, if I have more time, I'll investigate how to use the ATI proprietary driver and have 1600 x 1200 resolution. Otherwise, I might just break down and get an AGP GeForce 7600 GS video card from Newegg and quit messing with it.