GTX 260 is 10.5 inches long (and so are GTX 275/280/285/295)
The ATX motherboards are 9.6" wide.
Both Sonata III and Elite fit a 10.5" video card without a problem, especially since they side-mount the HDDs (no power or data cables intruding into area where a video card might be).
In this interior view of the Elite you can see the extra room between the right edge of the motherboard tray and the HDD cage. About a 1/2" to spare with the GTX 260 according to the NewEgg customer reviews.