Index: /trunk/src/VBox/Additions/WINNT/Graphics/Video/mp/wddm/VBoxMPWddm.cpp
===================================================================
--- /trunk/src/VBox/Additions/WINNT/Graphics/Video/mp/wddm/VBoxMPWddm.cpp	(revision 64742)
+++ /trunk/src/VBox/Additions/WINNT/Graphics/Video/mp/wddm/VBoxMPWddm.cpp	(revision 64743)
@@ -6691,5 +6691,4 @@
         Assert(pPresent->SubRectCnt > pPresent->MultipassOffset);
         UINT cbRects = (pPresent->SubRectCnt - pPresent->MultipassOffset) * sizeof (RECT);
-        pPresent->pDmaBufferPrivateData = (uint8_t*)pPresent->pDmaBufferPrivateData + cbHead + cbRects;
         pPresent->pDmaBuffer = ((uint8_t*)pPresent->pDmaBuffer) + VBOXWDDM_DUMMY_DMABUFFER_SIZE;
         Assert(pPresent->DmaSize >= VBOXWDDM_DUMMY_DMABUFFER_SIZE);
@@ -6702,4 +6701,6 @@
             memcpy(&pCF->ClrFill.Rects.aRects[pPresent->MultipassOffset], pPresent->pDstSubRects, cbRects);
             pCF->ClrFill.Rects.cRects += cbRects/sizeof (RECT);
+
+            pPresent->pDmaBufferPrivateData = (uint8_t*)pPresent->pDmaBufferPrivateData + cbHead + cbRects;
         }
         else
@@ -6707,9 +6708,11 @@
             UINT cbFitingRects = (cbCmd/sizeof (RECT)) * sizeof (RECT);
             Assert(cbFitingRects);
-            memcpy(&pCF->ClrFill.Rects.aRects[pPresent->MultipassOffset], pPresent->pDstSubRects, cbFitingRects);
+            memcpy(&pCF->ClrFill.Rects.aRects[0], pPresent->pDstSubRects, cbFitingRects);
             cbCmd -= cbFitingRects;
             pPresent->MultipassOffset += cbFitingRects/sizeof (RECT);
             pCF->ClrFill.Rects.cRects += cbFitingRects/sizeof (RECT);
             Assert(pPresent->SubRectCnt > pPresent->MultipassOffset);
+
+            pPresent->pDmaBufferPrivateData = (uint8_t*)pPresent->pDmaBufferPrivateData + cbHead + cbFitingRects;
             Status = STATUS_GRAPHICS_INSUFFICIENT_DMA_BUFFER;
         }