diff --git a/src/common/modeset/timing/nvt_dsc_pps.c b/src/common/modeset/timing/nvt_dsc_pps.c
index 4ed6c25a4..2ee862738 100644
--- a/src/common/modeset/timing/nvt_dsc_pps.c
+++ b/src/common/modeset/timing/nvt_dsc_pps.c
@@ -1010,7 +1010,7 @@ DSC_PpsCalcBase
         }
         else
         {
-            RANGE_CHECK("pic_width", in->pic_width, 32, 5120);
+            RANGE_CHECK("pic_width", in->pic_width, 32, DSC_MAX_SINGLE_HEAD_WIDTH);
         }
     }
 
diff --git a/src/common/modeset/timing/nvt_dsc_pps.h b/src/common/modeset/timing/nvt_dsc_pps.h
index bd49c1464..a13911ef8 100644
--- a/src/common/modeset/timing/nvt_dsc_pps.h
+++ b/src/common/modeset/timing/nvt_dsc_pps.h
@@ -34,6 +34,7 @@
 
 /* ------------------------ Macros ----------------------------------------- */
 #define DSC_MAX_PPS_SIZE_DWORD 32
+#define DSC_MAX_SINGLE_HEAD_WIDTH 5120
 
 /* ------------------------ Datatypes -------------------------------------- */
 typedef struct
diff --git a/src/nvidia-modeset/include/nvkms-evo.h b/src/nvidia-modeset/include/nvkms-evo.h
index 63cc8b953..bb790ae4e 100644
--- a/src/nvidia-modeset/include/nvkms-evo.h
+++ b/src/nvidia-modeset/include/nvkms-evo.h
@@ -196,8 +196,8 @@ NvBool nvDowngradeColorFormatAndBpc(
     const NvBool colorBpcSpecified,
     NVDpyAttributeColor *pDpyColor);
 
-NvBool nvDPValidateModeEvo(NVDpyEvoPtr pDpyEvo,
-                           NVHwModeTimingsEvoPtr pTimings,
+NvBool nvDPValidateModeEvo(const NVDpyEvoRec *pDpyEvo,
+                           const NVHwModeTimingsEvo *pTimings,
                            const NvBool colorFormatSpecified,
                            const NvBool colorBpcSpecified,
                            NVDpyAttributeColor *pDpyColor,
@@ -435,6 +435,9 @@ NvBool nvEvoGetSingleMergeHeadSectionHwModeTimings(
 
 NvBool nvEvoUse2Heads1OR(const NVDpyEvoRec *pDpyEvo,
                          const NVHwModeTimingsEvo *pTimings,
+                         const NVDpyAttributeColor *pDpyColor,
+                         const NvBool colorFormatSpecified,
+                         const NvBool colorBpcSpecified,
                          const struct NvKmsModeValidationParams *pParams);
 
 NvU32 nvGetRefreshRate10kHz(const NVHwModeTimingsEvo *pTimings);
diff --git a/src/nvidia-modeset/src/nvkms-evo.c b/src/nvidia-modeset/src/nvkms-evo.c
index 600003f0a..3b1cf25b8 100644
--- a/src/nvidia-modeset/src/nvkms-evo.c
+++ b/src/nvidia-modeset/src/nvkms-evo.c
@@ -7032,8 +7032,8 @@ NvBool nvDowngradeColorFormatAndBpc(
  * the given mode timings.
  */
 
-NvBool nvDPValidateModeEvo(NVDpyEvoPtr pDpyEvo,
-                           NVHwModeTimingsEvoPtr pTimings,
+NvBool nvDPValidateModeEvo(const NVDpyEvoRec *pDpyEvo,
+                           const NVHwModeTimingsEvo *pTimings,
                            const NvBool colorFormatSpecified,
                            const NvBool colorBpcSpecified,
                            NVDpyAttributeColor *pDpyColor,
@@ -9813,6 +9813,9 @@ NvBool nvEvoGetSingleMergeHeadSectionHwModeTimings(
 
 NvBool nvEvoUse2Heads1OR(const NVDpyEvoRec *pDpyEvo,
                          const NVHwModeTimingsEvo *pTimings,
+                         const NVDpyAttributeColor *pDpyColor,
+                         const NvBool colorFormatSpecified,
+                         const NvBool colorBpcSpecified,
                          const struct NvKmsModeValidationParams *pParams)
 {
     const NVDispEvoRec *pDispEvo = pDpyEvo->pDispEvo;
@@ -9846,9 +9849,29 @@ NvBool nvEvoUse2Heads1OR(const NVDpyEvoRec *pDpyEvo,
         return FALSE;
     }
 
-    /* Use 2Heads1OR mode only if the required pixel clock is greater than the
-     * maximum pixel clock support by a head. */
-    return (pTimings->pixelClock > pHeadCaps->maxPClkKHz);
+    if (pTimings->pixelClock > pHeadCaps->maxPClkKHz) {
+        return TRUE;
+    }
+
+    if (!nvDpyUsesDPLib(pDpyEvo) ||
+            (pParams->dscMode == NVKMS_DSC_MODE_FORCE_DISABLE) ||
+            (pTimings->yuv420Mode == NV_YUV420_MODE_HW) ||
+            (nvEvoVisibleWidth(pTimings) <= DSC_MAX_SINGLE_HEAD_WIDTH)) {
+        return FALSE;
+    }
+
+    /*
+     * A wide DSC picture needs two heads even when its pixel clock fits one.
+     * Preserve single-head modes that can already pass DP validation,
+     * including its existing uncompressed color-depth fallbacks.
+     */
+    NVDpyAttributeColor dpyColor = *pDpyColor;
+
+    return !nvDPValidateModeEvo(pDpyEvo, pTimings,
+                                colorFormatSpecified,
+                                colorBpcSpecified,
+                                &dpyColor, FALSE /* b2Heads1Or */,
+                                NULL /* pDscInfo */, pParams);
 }
 
 NvBool nvIsLockGroupFlipLocked(const NVLockGroup *pLockGroup)
diff --git a/src/nvidia-modeset/src/nvkms-modepool.c b/src/nvidia-modeset/src/nvkms-modepool.c
index 59dfd370d..6b42ee542 100644
--- a/src/nvidia-modeset/src/nvkms-modepool.c
+++ b/src/nvidia-modeset/src/nvkms-modepool.c
@@ -1721,7 +1721,10 @@ static NvBool ValidateMode(NVDpyEvoPtr pDpyEvo,
         goto done;
     }
 
-    b2Heads1Or = nvEvoUse2Heads1OR(pDpyEvo, pTimingsEvo, pParams);
+    b2Heads1Or = nvEvoUse2Heads1OR(pDpyEvo, pTimingsEvo, &dpyColor,
+                                   pDpyOutputColorParams->formatSpecified,
+                                   pDpyOutputColorParams->bpcSpecified,
+                                   pParams);
 
     if (nvDpyIsHdmiEvo(pDpyEvo)) {
         NvBool foundFrlConfig = FALSE;
diff --git a/src/nvidia-modeset/src/nvkms-modeset.c b/src/nvidia-modeset/src/nvkms-modeset.c
index f51f97bcf..d3809ca16 100644
--- a/src/nvidia-modeset/src/nvkms-modeset.c
+++ b/src/nvidia-modeset/src/nvkms-modeset.c
@@ -831,6 +831,9 @@ static NvBool AssignProposedHwHeadsGeneric(
             if (!nvEvoUse2Heads1OR(
                     pDpyEvo,
                     &pProposedApiHead->timings,
+                    &pProposedApiHead->attributes.color,
+                    pProposedApiHead->colorFormatSpecified,
+                    pProposedApiHead->colorBpcSpecified,
                     &pProposedApiHead->modeValidationParams)) {
                 continue;
             }
@@ -840,6 +843,9 @@ static NvBool AssignProposedHwHeadsGeneric(
             nvAssert(!nvEvoUse2Heads1OR(
                         pDpyEvo,
                         &pProposedApiHead->timings,
+                        &pProposedApiHead->attributes.color,
+                        pProposedApiHead->colorFormatSpecified,
+                        pProposedApiHead->colorBpcSpecified,
                         &pProposedApiHead->modeValidationParams));
 
             NvU32 foundHead = GetFreeHeads(pDevEvo, apiHead, pDpyEvo,
@@ -908,6 +914,9 @@ void ClearIncompatibleHwHeadsMaskOneDisp(const NVDispEvoRec *pDispEvo,
         const NvBool new2Heads1OrState =
             nvEvoUse2Heads1OR(pDpyEvo,
                               &pProposedApiHead->timings,
+                              &pProposedApiHead->attributes.color,
+                              pProposedApiHead->colorFormatSpecified,
+                              pProposedApiHead->colorBpcSpecified,
                               &pProposedApiHead->modeValidationParams);
 
         if (new2Heads1OrState != current2Heads1OrState) {