diff --git a/src/legacy_crtc.c b/src/legacy_crtc.c
index 4a7071a..733a883 100644
--- a/src/legacy_crtc.c
+++ b/src/legacy_crtc.c
@@ -1735,7 +1735,7 @@ legacy_crtc_mode_set(xf86CrtcPtr crtc, DisplayModePtr mode,
 
 	if (output->crtc == crtc) {
 	    if (radeon_output->MonType != MT_CRT)
-		pll_flags |= RADEON_PLL_NO_ODD_POST_DIV;
+		pll_flags |= (RADEON_PLL_NO_ODD_POST_DIV | RADEON_PLL_USE_REF_DIV);
 	    if (radeon_output->MonType == MT_LCD)
 		pll_flags |= (RADEON_PLL_USE_BIOS_DIVS | RADEON_PLL_USE_REF_DIV);
 	}