diff -up xf86-video-ati-6.12.1/src/radeon_driver.c.jx xf86-video-ati-6.12.1/src/radeon_driver.c
--- xf86-video-ati-6.12.1/src/radeon_driver.c.jx 2009-04-09 11:40:31.000000000 -0400
+++ xf86-video-ati-6.12.1/src/radeon_driver.c 2009-04-09 11:52:43.000000000 -0400
@@ -3089,6 +3089,15 @@ Bool RADEONPreInit(ScrnInfoPtr pScrn, in
} else if (IS_R300_VARIANT) {
crtc_max_X = 2560;
crtc_max_Y = 1200;
+ } else if (info->ChipFamily >= CHIP_FAMILY_R600) {
+ /* no kms, but also no 3d, so be a little aggressive */
+ if (pScrn->videoRam >= 128 * 1024) {
+ crtc_max_X = 4096;
+ crtc_max_Y = 1920;
+ } else {
+ crtc_max_X = 2560;
+ }
} else if (IS_AVIVO_VARIANT) {
crtc_max_Y = 1600;